title: IAI Kfir

text: As a result of a trade agreement between Colombia and Israel in 1989 the Colombian government bought a batch of 12 ex-IAF Kfir C.2s and one TC.2, which were delivered to the Colombian Air Force ("FAC") in 1989–1990. Since then, all the C.2s have been upgraded to the C.7 variant. The "FAC" Kfirs have been widely used in ground-attack missions during counter-insurgency operations against Colombian terrorists. Colombian Kfirs are armed with Python 3 IR-homing AAMs. As of 2004 two aircraft had been lost in accidents.


title: IAI Kfir

text: In February 2008, Colombia signed a deal with the Israeli government for an additional 24 ex-IAF Kfir aircraft. It was estimated that these aircraft will most probably be upgraded by Israel Aerospace Industries to C.10 standard.


title: IAI Kfir

text: In June 2009, IAI delivered the first batch of upgraded Kfirs to the Colombian Air Force in a ceremony held at IAI's facilities in Israel. In attendance at the ceremony was Juan Hurtado Cano, the Colombian Ambassador to Israel, high-ranking officers from the Colombian Air Force, and executives from the International Defense Cooperation Directorate of the Israeli Ministry of Defense (IMOD-SIBAT). This was a part of a multi-year contract awarded in late 2007 and worth over $150 million to upgrade the existing Colombian Air Force Kfirs, and to supply additional jets. The additional Kfir jets, models C.10-C.12, have been upgraded and improved to include IAI's latest technologies and products.


title: IAI Kfir

text: On July 20, 2009, a Kfir crashed near the city of Cartagena. The Israeli pilots operating the plane were unharmed in the incident, but the jet itself was destroyed. Israel Aerospace Industries said in a statement that the plane was flying a refresher flight, and that the aircraft didn't come to a stop on the landing strip, landing outside it. The director of the Israel Aerospace Industries announced that an investigation into the incident had already begun and that a panel to probe the crash had been appointed.


title: IAI Kfir

text: On July 22, 2009, Israel Aerospace Industries informed the Colombian Air Force that the accident was caused by an unspecified human error. As a result, Israel Aerospace Industries will replace the unit lost with another one and it will resume delivery to the Colombian Air Force.


title: IAI Kfir

text: On November 1, 2013, two Colombian Air Force IAI Kfirs intercepted Russian Air Force Tu-160s that had entered Colombian airspace. The Russian aircraft had taken off from Simón Bolívar International Airport Venezuela.


title: IAI Kfir

text: On October 10, 2017, Colombian IAI Kfirs were updated with the EL/M 2052 AESA Radar and incorporated the I-Derby-ER Active Air to Air Missile and the Python-5 Air to Air Infrared Missile


title: IAI Kfir

text: In 1981, Ecuador and Israel signed a sales agreement for ten refurbished and new ex-IAF Kfir C.2s and two TC.2s, which were delivered to the Ecuadorian Air Force ("FAE") in 1982–1983. The Kfirs formed the 2113rd Squadron ("Lions") of the FAE's 21st Fighter Wing, based at Taura AFB, on the Ecuadorian western lowlands.


title: IAI Kfir

text: The "FAE" Kfirs went into action during the 1995 Cenepa War between Ecuador and Peru. Relying on its fleet of subsonic A-37Bs for low-level ground-attack missions on Peruvian positions, the Ecuadorian Air Force held back its Mirage F.1s and Kfir C.2s for use as escorts and interceptors. On February 10, 1995, a Kfir C.2 shot down a Peruvian Air Force Cessna A-37B with a Shafrir 2 IR-homing AAM.


title: IAI Kfir

text: In 1996, with tensions still running high between Ecuador and Peru, the Ecuadorians acquired four additional Kfirs (three C.2 and one TC.2) after securing approval from the U.S. State Department.


title: IAI Kfir

text: In 1998, with its aging squadron of SEPECAT Jaguar fighter-bombers about to be withdrawn from active duty, Ecuador began talks with Israel for the sale of a new batch of eight Kfirs. Fearing an escalation of the arms race in South America (Peru had recently acquired 18 MiG-29s and 18 Su-25s from Belarus), the United States blocked the deal. As an alternative, Ecuador and Israel signed an agreement in 1999 for the delivery of two Kfir C.10s and for the conversion of an undisclosed number of the "FAE's" original C.2s to the C.10 version, referred to in Ecuador as Kfir CE, featuring a Helmet Mounted Display System, and armed with Python 3 and Python 4 IR-homing AAMs.


title: IAI Kfir

text: By 2005, Ecuador had lost four Kfirs, including one TC.2, due to accidents since the aircraft entered service in 1982.


title: IAI Kfir

text: The Sri Lanka Air Force (SLAF) acquired six Kfir C.2s and a single TC.2 in 1995–1996. A further nine aircraft had been added to the inventory by 2005, including four C.2s and four C.7s acquired in 2000. Currently the SLAF operates two TC.2s, two C.7s and six C.2s by the No. 10 "Fighter" Squadron. The SLAF used their Kfirs to carry out attacks against LTTE rebels during the Sri Lankan Civil War in Sri Lanka. Two Kfir C.7s were destroyed on the ground in an LTTE attack on SLAF Katunayake air base, part of Bandaranaike International Airport, on 24 July 2001. Three others were lost in non-combat related accidents during the Civil War period. None were lost in aerial combat. In March 2011, two Kfirs collided in mid-air during an airshow practice sortie.


title: IAI Kfir

text: On June 30, 2021, it was announced that the IAI will upgrade five Sri Lankan Kfirs for a return to service with new systems and sensors under a US$50 million contract.


title: IAI Kfir

text: Between 1985 and 1989, the United States Navy and United States Marine Corps leased 25 examples of the Kfir C.1, which were officially designated F-21A and modified for use as unarmed adversaries: mock opponents in dissimilar air combat training (DACT). These aircraft had narrow-span canard foreplanes and two small rectangular strakes, one on either side of the nose, which considerably improved the aircraft's maneuverability and handling at low speeds.


title: IAI Kfir

text: The 12 F-21 aircraft leased to the U.S. Navy, painted in a three-tone blue-gray "ghost" scheme, were operated by Fighter Squadron 43 (VF-43), based at NAS Oceana, Virginia. In 1988, they were returned and replaced by the F-16N. The 13 aircraft leased to the U.S. Marine Corps were operated by Marine Fighter Training Squadron 401 (VMFT-401), a 4th Marine Aircraft Wing/ Marine Corps Reserve squadron at Marine Corps Air Station Yuma, Arizona. In addition to the blue-gray painted aircraft, the USMC also had some F-21s painted in Israeli colors and desert "flogger" schemes (named because they were to represent the schemes often worn by Warsaw Pact MiG-23 "Floggers"). The Kfir was utilized because they both shared the common characteristic of being very fast (Mach 2+) and fast-accelerating aircraft with relatively poor maneuverability. The MiG-23 was targeted as the "enemy" aircraft because at this time the MiG-23 was being introduced in very large numbers, and was a very capable aircraft compared to earlier Soviet types. These USMC F-21 aircraft were replaced by F-5E aircraft when the F-21s were returned in 1989 (although this left the training units without any aircraft capable of accurately simulating the Mach 2+ and fast-accelerating MiG-23).


title: IAI Kfir

text: Six Kfirs are also used by the US firm Airborne Tactical Advantage Company (ATAC), a civilian defense contractor that provides tactical adversary aircraft services to the US military. ATAC provides airborne tactical training, threat simulation, and research & development. ATAC's corporate headquarters and primary operating location is at Patrick Henry International Airport in Newport News, VA, with additional permanent operating locations at US Naval Air Stations and Marine Corps Air Stations in California, Nevada, Hawaii and Japan. ATAC also operates Hawker Hunter F.58s. On March 6, 2012, an ATAC Kfir, FAA registration N404AX, crashed while landing at NAS Fallon, Nevada after a flight supporting the Naval Strike and Air Warfare Center. The pilot, retired USN Captain Carroll "Lex" LeFon, was fatally injured.


title: IAI Kfir

text: In the early 1990s, IAI was looking to export 40 Kfir-C fighters to the Republic of China (Taiwan) in a deal estimated to have been worth US$400 million to $1 billion; however, the deal ultimately fell through.


title: IAI Kfir

text: During 2013, the Argentine Air Force commenced negotiations with Israel for 18 Kfir Block 60 fighters as an alternative to another deal for 16 ex-Spanish Mirage F1 fighters. During mid-2014, industry sources claim IAI will "soon" receive an order from the Argentine Air Force for Kfir Block 60s after their purchase of surplus Spanish Mirage F1s failed.


title: Names of God

text: There are various names of God, many of which enumerate the various qualities of a Supreme Being. The English word "god" (and its equivalent in other languages) is used by multiple religions as a noun to refer to different deities, or specifically to the Supreme Being, as denoted in English by the capitalized and uncapitalized terms "God" and "god". Ancient cognate equivalents for the biblical Hebrew "Elohim", one of the most common names of God in the Bible, include proto-Semitic "El", biblical Aramaic "Elah", and Arabic "'ilah". The personal or proper name for God in many of these languages may either be distinguished from such attributes, or homonymic. For example, in Judaism the tetragrammaton is sometimes related to the ancient Hebrew "ehyeh" ("I will be"). In the Hebrew Bible (), YHWH, the personal name of God, is revealed directly to Moses. Correlation between various theories and interpretation of the name of "the one God", used to signify a monotheistic or ultimate Supreme Being from which all other divine attributes derive, has been a subject of ecumenical discourse between Eastern and Western scholars for over two centuries. In Christian theology the word is considered a personal and a proper name of God. On the other hand, the names of God in a different tradition are sometimes referred to by symbols. The question whether divine names used by different religions are equivalent has been raised and analyzed.


title: Names of God

text: Exchange of names held sacred between different religious traditions is typically limited. Other elements of religious practice may be shared, especially when communities of different faiths are living in close proximity (for example, the use of Khuda or Prabhu within the Indian Christian community) but usage of the names themselves mostly remains within the domain of a particular religion, or even may help define one's religious belief according to practice, as in the case of the recitation of names of God (such as the japa). Guru Gobind Singh's Jaap Sahib, which contains 950 names of God is one example of this. "The Divine Names", the classic treatise by Pseudo-Dionysius, defines the scope of traditional understandings in Western traditions such as Hellenic, Christian, Jewish and Islamic theology on the nature and significance of the names of God. Further historical lists such as "The 72 Names of the Lord" show parallels in the history and interpretation of the name of God amongst Kabbalah, Christianity, and Hebrew scholarship in various parts of the Mediterranean world.


title: Names of God

text: The attitude as to the transmission of the name in many cultures was surrounded by secrecy. In Judaism, the pronunciation of the name of God has always been guarded with great care. It is believed that, in ancient times, the sages communicated the pronunciation only once every seven years; this system was challenged by more recent movements.


title: Names of God

text: The nature of a holy name can be described as either personal or attributive. In many cultures it is often difficult to distinguish between the personal and the attributive names of God, the two divisions necessarily shading into each other.


title: Names of God

text: El comes from a root word meaning "god" or "deity", reconstructed in the Proto-Semitic language as "ʾil". Sometimes referring to God and sometimes the mighty when used to refer to the God of Israel, El is almost always qualified by additional words that further define the meaning that distinguishes him from false gods. A common title of God in the Hebrew Bible is Elohim (Hebrew: ). The root "Eloah" () is used in poetry and late prose (e.g., the Book of Job) and ending with the masculine plural suffix "-im" creating a word like "ba`alim" ("owner(s)") and "adonim" ("lord(s), master(s)") that may also indicate a singular identity.


title: Names of God

text: In the Book of Exodus, God commands Moses to tell the people that 'I AM' sent him, and this is revered as one of the most important names of God according to Mosaic tradition.


title: Names of God

text: In , when Moses first spoke with God, God said, "I used to appear to Abraham, Isaac, and Jacob as El Shaddai, but I did not make myself known to them by my name YHWH."


title: Names of God

text: YHWH () is the proper name of God in Judaism. Neither vowels nor vowel points were used in ancient Hebrew writings and the original vocalisation of YHWH has been lost.


title: Names of God

text: Later commentaries additionally suggested that the true pronunciation of this name is composed entirely of vowels, such as the Greek . However, this is put into question by the fact that vowels were only distinguished in the time-period by their very absence due to the lack of explicit vowels in the Hebrew script. The resulting substitute made from semivowels and glottals, known as the tetragrammaton, is not ordinarily permitted to be pronounced aloud, even in prayer. The prohibition on misuse (not use) of this name is the primary subject of the command not to take the name of the Lord in vain.


title: Names of God

text: Instead of pronouncing YHWH during prayer, Jews say "Adonai" ("Lord"). "Halakha" requires that secondary rules be placed around the primary law, to reduce the chance that the main law will be broken. As such, it is common religious practice to restrict the use of the word "Adonai" to prayer only. In conversation, many Jewish people, even when not speaking Hebrew, will call God "HaShem" (), which is Hebrew for "the Name" (this appears in ).


title: Names of God

text: Almost all Orthodox Jews avoid using either Yahweh or Jehovah altogether on the basis that the actual pronunciation of the tetragrammaton has been lost in antiquity. Many use the term "HaShem" as an indirect reference, or they use "God" or "The Lord" instead. Mark Sameth argues that Yahweh was a pseudo name for a dual-gendered deity, the four letters of that name being cryptogram which the priests of ancient Israel read in reverse as , "heshe," as earlier theorized by Guillaume Postel (16th century) and (19th century).


title: Names of God

text: In Christianity, the Old Testament reveals YHWH (; often vocalized with vowels as "Yahweh" or "Jehovah") as the personal name of God. References, such as "The New Encyclopædia Britannica", affirm the vocalization "Yahweh" by offering additional specifics to its (Christian) reconstruction out of Greek sources:


title: Names of God

text: Early Christian writers, such as Clement of Alexandria in the 2nd century, had used a form like Yahweh, and claim that this pronunciation of the tetragrammaton was never really lost. Other Greek transcriptions also indicated that YHWH should be pronounced Yahweh.


title: Names of God

text: Jah or Yah (rendered as in Hebrew) is an abbreviation of Jahweh/Yahweh/Jehovah. It appears in certain translations of the Bible, such as the Revised Standard Version, and is used by Christians in the interjection Hallelujah, meaning "Praise Jah", which is used to give Jahweh glory. In Christianity, certain hymns dedicated to God invoke the divine name using the vocalization Jehovah (, ), such as "Guide Me, O Thou Great Jehovah".


title: Names of God

text: The Hebrew personal name of God YHWH is rendered as "the " in many translations of the Bible, with Elohim being rendered as "God"; certain translations of Scripture render the Tetragrammaton with Yahweh or Jehovah in particular places, with the latter vocalization being used in the King James Version, Tyndale Bible, and other translations of the Bible from that time period and later. Many English translations of the Bible translate the tetragrammaton as , thus removing any form of YHWH from the written text and going well beyond the Jewish oral practice of substituting Adonai for YHWH when reading aloud.


title: Names of God

text: English Bible translations of the Greek New Testament render (Greek: ) as God and (Greek: ) as "the Lord", with the latter being the "Greek translation of the Hebrew OT name for God, Yahweh."


title: Names of God

text: Jesus (Iesus, Yeshua) was a common alternative form of the name ( – Joshua) in later books of the Hebrew Bible and among Jews of the Second Temple period. The name corresponds to the Greek spelling , from which comes the English spelling "Jesus". "Christ" means 'the anointed' in Greek (). is the Greek equivalent of the Hebrew word Messiah; while in English the old Anglo-Saxon Messiah-rendering (healer) was practically annihilated by the Latin , some cognates such as in Dutch and Afrikaans survive—also, in German, the word is sometimes used as reference to Jesus, e.g., in church chorals).


title: Names of God

text: In the Book of Revelation in the Christian New Testament, God is quoted as saying "I am the Alpha and the Omega, the First and the Last, the Beginning and the End". (cf. , , and )


title: Names of God

text: Some Quakers refer to God with the title of the Light. Another term used is King of Kings or Lord of Lords and Lord of Hosts. In addition to the personal name of God YHWH (pronounced with the vocalizations Yahweh or Jehovah), titles of God used by Christians include the Hebrew titles Elohim, El-Shaddai, and Adonai, as well as Ancient of Days, Father/Abba which is Hebrew, "Most High". "Abba" ('father' in Hebrew) is a common term used for the creator within Christianity because it was a title Jesus used to refer to God the Father.


title: Names of God

text: In Mormonism the name of God the Father is Elohim and the name of Jesus in his pre-incarnate state was Jehovah. Together, with the Holy Ghost they form the Godhead; God the Father, Jesus Christ, and the Holy Spirit. Mormons typically refer to God as "Heavenly Father" or "Father in Heaven".


title: Names of God

text: Although Mormonism views the Father, the Son, and the Holy Spirit as three distinct beings, they are one in purpose and God the Father (Elohim) is worshipped and given all glory through his Son, Jesus Christ (Jehovah). Despite the Godhead doctrine, which teaches that God the Father, Jesus Christ and the Holy Ghost are three separate, divine beings, many Mormons (mainstream Latter-day Saints and otherwise, such as the Fundamentalist Church of Jesus Christ of Latter-Day Saints) view their beliefs as monotheist since Christ is the conduit through which humanity comes to the God the Father. The Book of Mormon ends with "to meet you before the pleasing bar of the great Jehovah, the eternal Judge of both the quick and dead. Amen."


title: Names of God

text: Jehovah's Witnesses believe that God has only one distinctive name, represented in the Old Testament by the Tetragrammaton. In English, they prefer to use the form Jehovah. According to Jehovah's Witnesses, the name Jehovah means "He causes to become".


title: Names of God

text: Scriptures frequently cited in support of the name include Isaiah 42:8: "I am Jehovah. That is my name", Psalms 83:18: "May people know that you, whose name is Jehovah, You alone are the Most High over all the earth", and Exodus 6:3: "And I used to appear to Abraham, Isaac, and Jacob as God Almighty, but with regard to my name Jehovah I did not make myself known to them."


title: Names of God

text: While opposers of the faith critique their use of the form "Jehovah", Jehovah's Witnesses still hold on to their belief that, despite having scholars prefer the "Yahweh" pronunciation, the name Jehovah adequately transmits the idea behind the meaning of God's name in English. While they do not discourage the use of the "Yahweh" pronunciation, they highly consider the long history of the name Jehovah in the English language and see that it sufficiently identifies God's divine persona. This rationale is analogous to the widespread use of Jesus as the English translation of .


title: Names of God

text: Allah—meaning 'the God' in Arabic—is the word for God in Islam. The word "Allah" has been used by Arabic people of different religions since pre-Islamic times. More specifically, it has been used as a term for God by Muslims (both Arab and non-Arab) and Arab Christians. God has many names in Islam. The Qur'an says (in translation) "to Him Belong the Best Names ()"; examples include "Ar-Rahman" ('the Entirely Merciful') and ('the Especially Merciful'). Beside these Arabic names, Muslims of non-Arab origins may also sometimes use other names in their own languages to refer to God, such as "Khuda" in Persian, Bengali and Urdu. or "Tengri" was used in the Ottoman Turkish language as the equivalent of Allah.


title: Names of God

text: In Tasawwuf, the inner, mystical dimension of Islam, Hu, (depends on placement in the sentence), or "Parvardigar" in Persian are used as names of God. The sound derives from the last letter of the word Allah, which is read as when in the middle of a sentence. means 'Just He' or 'Revealed'. The word explicitly appears in many verses of the Quran:


title: Names of God

text: The scriptures of the Baháʼí Faith often refer to God by various titles and attributes, such as Almighty, All-Possessing, All-Powerful, All-Wise, Incomparable, Gracious, Helper, All-Glorious, and Omniscient. Baháʼís believe the Greatest Name of God is "All-Glorious" or ' in Arabic. ' is the root word of the following names and phrases: the greeting ' ('God is the All-Glorious'), the invocation ' ('O Thou Glory of the Most Glorious'), "" ('the Glory of God'), and ('Follower of the All-Glorious'). These are expressed in Arabic regardless of the language in use (see Baháʼí symbols). Apart from these names, God is addressed in the local language, for example in Hindi, in French and in Spanish. Baháʼís believe Bahá'u'lláh, the founder of the Baháʼí Faith, is the "complete incarnation of the names and attributes of God".


title: Names of God

text: Mandaeans believe in one God called ('The Great Life' or 'The Great Living God'). Other names for God used include ('Lord of Greatness'), ('The Great Mind'), ('King of Light') and ('The First Life').


title: Names of God

text: There are multiple names for God's various manifestations worshiped in Hinduism. Some of the common names for these deities in Hinduism are:


title: Names of God

text: Additionally, most Hindu deities have a collection of 8/12/16/32/100/108/1000/1008 names exclusively dedicated to them known as .


title: Names of God

text: Maharishi Dayanand in his book "Vaghasiya Ayush" has listed 100 names of God each representing some property or attribute thereof mentioning "Om" or "Aum" as God's personal and natural name.


title: Names of God

text: Jainism rejects the idea of a creator deity responsible for the manifestation, creation, or maintenance of this universe. According to Jain doctrine, the universe and its constituents (soul, matter, space, time, and principles of motion) have always existed. All the constituents and actions are governed by universal natural laws and an immaterial entity like God cannot create a material entity like the universe. Jainism offers an elaborate cosmology, including heavenly beings ("s"), but these beings are not viewed as creators; they are subject to suffering and change like all other living beings, and must eventually die.


title: Names of God

text: Jains define godliness as the inherent quality of any soul characterizing infinite bliss, infinite power, perfect knowledge and perfect peace. However, these qualities of a soul are subdued due to karmas of the soul. One who achieves this state of soul through right belief, right knowledge and right conduct can be termed as god. This perfection of soul is called "kaivalya" (omniscience). A liberated soul thus becomes a god – liberated of miseries, cycles of rebirth, world, "karmas" and finally liberated of body as well. This is called "nirvana" or "moksha".


title: Names of God

text: If godliness is defined as the state of having freed one's soul from karmas and the attainment of enlightenment/Nirvana and a god as one who exists in such a state, then those who have achieved such a state can be termed gods/"Tirthankara". Thus, Rishabhanatha was god/ but he was not the only ; there were many other . However, the quality of godliness is one and the same in all of them.


title: Names of God

text: Jainism does not teach the dependency on any supreme being for enlightenment. The is a guide and teacher who points the way to enlightenment, but the struggle for enlightenment is one's own. Moral rewards and sufferings are not the work of a divine being, but a result of an innate moral order in the cosmos; a self-regulating mechanism whereby the individual reaps the fruits of his own actions through the workings of the karmas.


title: Names of God

text: Jains believe that to attain enlightenment and ultimately liberation from all karmic bonding, one must practice the ethical principles not only in thought, but also in words (speech) and action. Such a practice through lifelong work towards oneself is called as observing the "Mahavrata" ('Great Vows').


title: Names of God

text: Gods can be thus categorized into embodied gods also known as "Tīrthankaras and Arihantas" or ordinary "Kevalis", and non-embodied formless gods who are called "Siddhas". Jainism considers the "s" and "s" to be souls who dwell in heavens owing to meritorious deeds in their past lives. These souls are in heavens for a fixed lifespan and even they have to undergo reincarnation as humans to achieve .


title: Names of God

text: In the Sikh scripture, both Hindu and Muslim names of the Supreme Being are also commonly employed, expressing different aspects of the divine Name. For instance, names like Ram ('pervading'), Hari ('shining'), Parmeshwar ('supreme lord'), and ('world lord') refer to Hindu terms, while names like Allah (Arabic for "God"), Khuda (Persian for "God"), Rahim ('merciful'), Karim ('generous'), and Sahib ('lord') are of Muslim origin.


title: Names of God

text: God, according to Guru Nanak, is beyond full comprehension by humans; has an endless number of virtues; takes on innumerable forms, but is formless; and can be called by an infinite number of names thus "Your Names are so many, and Your Forms are endless. No one can tell how many Glorious Virtues You have."


title: Names of God

text: The word "Allah" () is used 12 times in the "Guru Granth Sahib" (primary religious scripture) by Sheikh Farid. Guru Nanak Dev, Guru Arjan Dev and Bhagat Kabeer used the word 18 times.


title: Names of God

text: Yazidism knows only one eternal God, often named . According to some Yazidi hymns (known as "s"), God has 1001 names.


title: Names of God

text: In Zoroastrianism, 101 names of God (Pazand ) is a list of names of God (Ahura Mazda). The list is preserved in Persian, Pazand and Gujarati. Parsi tradition expanded this to a list of 101 names of God.


title: Names of God

text: Chukwu is the supreme being of the Odinani religion of the Igbo people. In the Igbo pantheon, Chukwu is the source of all other Igbo deities and is responsible for assigning them their different tasks. The Igbo people believe that all things come from Chukwu, who brings the rain necessary for plants to grow and controls everything on Earth and the spiritual world. They believe Chukwu to be an undefinable omnipotent and omnipresent supreme deity that encompasses everything in space and space itself. Igbo Christians also refer to the Abrahamic God as Chukwu.


title: Names of God

text: Nana Buluku is the female supreme being in West African Vodun. In Dahomey mythology, Nana Buluku is the mother supreme creator who gave birth to the moon spirit Mawu, the sun spirit Lisa, and all of the universe. After giving birth to these, she retired and left the matters of the world to Mawu-Lisa. She is the primary creator, Mawu-Lisa the secondary creator, and the theology based on these is called Vodun, Voodoo or Vodoun.


title: Names of God

text: The supreme creator in the traditional religion of the Yoruba people is known as Olorun or Olodumare. The Yoruba believe that Olodumare is omnipotent and is the source of all. Olodumare is aloof; he is not directly involved in earthly matters and lets other Yoruba deities (orisha), who are his sons and daughters, answer human concerns through divination, possession, sacrifice and more. However, everything is in the hands of Olodumare when they are going to bed at night. Yoruba Muslims and Christians also refer to the Abrahamic God as Olorun.


title: Names of God

text: Unkulunkulu is the supreme creator in Zulu traditional religion. Unkulunkulu brought human beings and cattle from an area of reeds. He created everything, from land and water, to man and the animals. He is considered the first man as well as the parent of all Zulu. He taught the Zulu how to hunt, how to make fire, and how to grow food. Zulu Christians also refer to the Abrahamic God as Unkulunkulu.


title: La Haine

text: La Haine (, ; released in the United States as Hate) is a 1995 French crime drama film written, co-edited, and directed by Mathieu Kassovitz. Starring Vincent Cassel, Hubert Koundé and Saïd Taghmaoui, the film chronicles a day and night in the lives of three friends from a poor immigrant neighbourhood in the suburbs of Paris. The title derives from a line spoken by one of them, Hubert: "", "hatred breeds hatred". Kassovitz was awarded the Best Director prize at the 1995 Cannes Film Festival.


title: La Haine

text: "La Haine" opens with a montage of news footage of urban riots in a "banlieue" in the commune of Chanteloup-les-Vignes near Paris. A local man, Abdel Ichaha, is in intensive care having been gravely injured in police custody. In the ensuing riots the local police station is besieged, and a police officer loses his revolver. The film depicts approximately twenty consecutive hours in the lives of three friends of Abdel, all young men from immigrant families, in the aftermath of the riot.


title: La Haine

text: Vinz is a young Jewish man with an aggressive temperament who wishes to avenge Abdel, has a blanket condemnation of all police officers, and secretly reenacts Travis Bickle from "Taxi Driver" in the bathroom mirror. Hubert is an Afro-French boxer and small-time drug dealer who yearns to leave the "banlieue" for a better life and refuses to provoke the police, but whose boxing gymnasium was burned down in the riots. Saïd is a young North African Muslim who plays a mediating role between Vinz and Hubert.


title: La Haine

text: The three go through an aimless daily routine, frequently finding themselves under police scrutiny. After the police break a rooftop gathering and the three sit idly on a playground, Vinz reveals to the other two that he has found the .44 Magnum revolver lost in the riot, and plans to use it to kill a police officer if Abdel dies. Although Hubert disapproves, Vinz secretly takes the gun with him. The three go to see Abdel in the hospital, but are turned away by the police. Saïd is arrested after their aggressive refusal to leave. He is later released with the help of a familiar police officer.


title: La Haine

text: Following a disagreement between Vinz and Hubert about their perspectives on policing and violence, the two men part ways. Saïd accompanies Vinz, while Hubert briefly returns to his home. They reunite at another gathering in the banlieue, but the situation quickly turns chaotic when Abdel's brother attempts to kill a police officer in revenge. A confrontation with the police ensues, and the group narrowly escapes after Vinz nearly shoots a riot officer. They take a train to Paris, where their responses to both benign and malicious Parisians cause several situations to escalate to dangerous hostility. In a public restroom, a Gulag survivor tells them of a friend who refused to relieve himself in public and subsequently froze to death, puzzling the three as to the meaning of the story.


title: La Haine

text: They then go to see Snoopy, an avid cocaine user who owes Saïd money, leading to a violent confrontation as he appears to try to force Vinz to play Russian roulette (the gun is secretly unloaded). They have a run-in with sadistic plainclothes police, who arrest Saïd and Hubert while Vinz flees. The police verbally and physically abuse the duo and lock them up until late night, which results in the three missing the last train from Saint-Lazare station and spending the night on the streets.


title: La Haine

text: After being kicked out of an art gallery and unsuccessfully trying to hotwire a car, the trio stay in a shopping mall and learn from a news broadcast that Abdel is dead. They travel to a rooftop from which they insult skinheads and policemen, before encountering the same group of skinheads who begin to beat Saïd and Hubert savagely. Vinz breaks up the fight at gunpoint and captures one of the skinheads. His plan to execute him is thwarted by his reluctance to go through with the deed, and, cleverly goaded by Hubert, he is forced to confront the fact that his heartless gangster pose does not reflect his true nature. Vinz lets the skinhead flee.


title: La Haine

text: Early in the morning, the trio return home and Vinz turns the gun over to Hubert. Vinz and Saïd encounter a plainclothes officer whom Vinz had insulted earlier whilst with his friends on a local rooftop. The officer grabs and threatens Vinz, taunting him with a loaded gun held to his head. Hubert rushes to their aid, but the officer's gun accidentally goes off, killing Vinz. As Hubert and the officer point their guns at each other and Saïd closes his eyes, a single gunshot is heard, with no indication of who fired or who may have been hit.


title: La Haine

text: This stand-off is underlined by a voice-over of Hubert's slightly modified opening lines ("It's about a society in free fall..."), underlining the fact that, as the lines say, "jusqu'ici tout va bien" ("so far so good"); all seems to be going relatively well until Vinz is killed, and from there no one knows what will happen, a microcosm of French society's descent through hostility into pointless violence.


title: La Haine

text: Kassovitz has said that the idea came to him when a young Zairian, , was shot in 1993. He was killed at point blank range while in police custody and handcuffed to a radiator. The officer was reported to have been angered by Makome's words, and had been threatening him when the gun went off accidentally. Kassovitz began writing the script on 6 April 1993, the day M'Bowole was shot. He was also inspired by the case of Malik Oussekine, a 22-year-old student protester who died after being badly beaten by the riot police after a mass demonstration in 1986, in which he did not take part. Oussekine's death is also referred to in the opening montage of the film. Mathieu Kassovitz included his own experiences; he took part in riots, he acts in a number of scenes and includes his father Peter in another.


title: La Haine

text: The majority of the filming was done in the Parisian suburb of Chanteloup-les-Vignes. Unstaged footage was used for this film, taken from 1986 to 1996; riots still took place during the time of filming. To actually film in the projects, Kassovitz, the production team and the actors, moved there for three months prior to the shooting as well as during actual filming. Due to the film's controversial subject matter, seven or eight local French councils refused to allow the film crew to film on their territory. Kassovitz was forced to temporarily rename the script "Droit de Cité". Some of the actors were not professionals and the film includes many situations that were based on real events.


title: La Haine

text: The music of the film was handled by French hardcore rap group Assassin, whose song "Nique la Police" (translated as "Fuck the Police") was featured in one of the scenes of the film. One of the members of Assassin, Mathias "Rockin' Squat" Crochon, is the brother of Vincent Cassel, who plays Vinz in the film.


title: La Haine

text: Upon its release, "La Haine" received widespread critical acclaim and was well received in France and abroad. The film was shown at the 1995 Cannes Film Festival where it enjoyed a standing ovation. Kassovitz was awarded the Best Director prize at the festival. The film opened at number one at the French box office with a gross of 12.5 million Francs for the week. It was number one for four consecutive weeks. The film had a total of 2,042,070 admissions in France where it was the 14th highest-grossing film of the year.


title: La Haine

text: On the review aggregator website Rotten Tomatoes, the film holds an approval rating of 100% based on 33 reviews, with an average rating of 8.2/10. The website's critics consensus reads, "Hard-hitting and breathtakingly effective, "La Haine" takes an uncompromising look at long-festering social and economic divisions affecting 1990s Paris." Kevin Thomas of the "Los Angeles Times" called the film "raw, vital and captivating". Wendy Ide of "The Times" stated that "La Haine" is "[o]ne of the most blisteringly effective pieces of urban cinema ever made."


title: La Haine

text: After the film was well received upon its release in France, Alain Juppé, who was Prime Minister of France at the time, commissioned a special screening of the film for the cabinet, which ministers were required to attend. A spokesman for the Prime Minister said that, despite resenting some of the anti-police themes present in the film, Juppé found "La Haine" to be "a beautiful work of cinematographic art that can make us more aware of certain realities."


title: La Haine

text: "La Haine" was available on VHS in the United States, but was not released on DVD until The Criterion Collection released a two-disc edition in 2007. Both HD DVD and Blu-ray versions have also been released in Europe, and Criterion released the film on Blu-ray in May 2012. The release includes audio commentary by Kassovitz, an introduction by actress Jodie Foster, "Ten Years of "La Haine"", a documentary that brings together cast and crew a decade after the film's landmark release, a featurette on the film's banlieue setting, production footage, and deleted and extended scenes, each with an afterword by Kassovitz.


title: Misery (novel)

text: Misery is an American psychological horror thriller novel written by Stephen King and first published by Viking Press on June 8, 1987. The novel's narrative is based on the relationship of its two main characters – the romance novelist Paul Sheldon and his deranged self-proclaimed number one fan Annie Wilkes. When Paul is seriously injured following a car accident, former nurse Annie brings him to her home, where Paul receives treatment and doses of pain medication. Paul realizes that he is a prisoner and is forced to indulge his captor's whims.


title: Misery (novel)

text: The novel's title has two meanings: it is the name carried by the central heroine of Paul's book series, and King described such a state of emotion during the novel's writing. He has stated that Annie is a stand-in for cocaine. King has outlined the creation of "Misery" in his memoirs, and mentioned that the image of Annie Wilkes came to him in a dream. King planned the book to be released under the pseudonym Richard Bachman, but his identity was discovered before the book's release.


title: Misery (novel)

text: "Misery" won the first Bram Stoker Award for Novel in 1987 and was nominated for the 1988 World Fantasy Award for Best Novel. Critical reception of "Misery" was positive – reviewers praised King for avoiding the fantasy elements of his past works, and noted the novel's parallels with King's personal life and the study of the relationship between celebrities and their fans. The novel, which took fourth place in the 1987 bestseller list, was adapted into an Academy Award-winning film directed by Rob Reiner in 1990, and into a theatrical production starring Laurie Metcalf and Bruce Willis in 2015.


title: Misery (novel)

text: Paul Sheldon is the author of the best-selling series of Victorian era romance novels featuring the character Misery Chastain, which he privately disdains. He has thus written the final installment, "Misery's Child", in which Misery is killed off. After completing the manuscript for his new crime novel, "Fast Cars", which he hopes will receive serious literary acclaim and kickstart his post-"Misery" career, Paul gets drunk and drives to Los Angeles instead of flying back home to New York City. He is caught in a snowstorm and crashes his car in the small, remote town of Sidewinder, Colorado.


title: Misery (novel)

text: He awakens to find that he has been rescued by Annie Wilkes, a local former nurse who is a devoted fan of the "Misery" series. She keeps Paul in her guest bedroom, refuses to take him to the hospital despite his broken legs, and nurses him herself using her illicit stash of codeine-based painkillers. Paul quickly becomes addicted to a medication named Novril, which Annie withholds in order to threaten and manipulate him. She begins reading the recently published "Misery's Child" and coerces permission to read the "Fast Cars" manuscript, but disapproves of the darker subject matter and profanity. Paul assesses that Annie is mentally unstable: she is prone to trailing off into catatonic episodes and has sudden, unpredictable bouts of rage. When she learns of Misery's death, she leaves Paul alone in her house for over two days, depriving him of food, water, and painkillers. During this time, Paul examines his legs and sees that they have been pulverized and deformed in the car crash.


title: Misery (novel)

text: Upon Annie's return, she forces a weakened Paul to burn the "Fast Cars" manuscript in exchange for his painkillers. Annie sets up an office for Paul – consisting of an antique Royal typewriter with a non-functional N-key, writing paper, and a wheelchair – for the purpose of writing a new "Misery" novel that will bring the character back from the dead. Biding his time and likening himself to Scheherezade, Paul begins a new book, "Misery's Return", and allows Annie to read the work in progress and fill in the missing N's. As Paul writes, the text includes excerpts of "Misery's Return", a macabre story in which it is found that Misery was buried alive while comatose.


title: Misery (novel)

text: Paul manages to escape his room using his wheelchair on several occasions, searching for more painkillers and exploring the house. He discovers a scrapbook full of newspaper clippings about deaths that reveal Annie to be a serial killer; her victims include a neighboring family, her own father, her roommate and, while she worked as a head nurse, many elderlies or critically injured patients and eleven infants, the last resulting in her standing trial but being acquitted in Denver. When Annie discovers that Paul has been leaving his room, she punishes him by cutting off his foot with an axe and cauterizing his ankle with a blowtorch, "hobbling" him.


title: Misery (novel)

text: Months later, Paul remains Annie's captive. After he complains that more typewriter keys had broken and refuses to tell Annie how the novel ends before he has written it, she cuts off his thumb with an electric knife.


title: Misery (novel)

text: A state trooper arrives at Annie's house in search of Paul, and Annie murders the officer by running him over with her riding lawnmower. Annie hides the remains, but the trooper's disappearance draws attention from law enforcement and the media. Annie relocates Paul to the basement. It becomes clear that she does not intend to let him live. After "Misery's Return" is finished, Paul lights a decoy copy of the manuscript on fire, which Annie attempts to save. Paul throws the typewriter at Annie and engages her in a violent fight; he manages to escape the bedroom and lock Annie inside. Paul then hides and alerts the police when they return in search of the murdered trooper. Annie is found dead from her injuries in the barn — she apparently escaped through a window and was on her way to murder Paul with a chainsaw.


title: Misery (novel)

text: After Paul has returned to New York, "Misery's Return" is set to be published and becomes an international bestseller due to the interest in the circumstances under which it was written. Paul resists the suggestion to write a nonfiction account of his own experiences. He is able to walk with a prosthesis but still struggles with nightmares about Annie, withdrawal from painkillers, alcoholism, and writer's block. When Paul finds random inspiration to write a new story, he weeps both for his shattered life and in the joy that he is finally able to write again.


title: Misery (novel)

text: One of Stephen King's inspirations for "Misery" was the reaction his fans had to his 1984 novel "The Eyes of the Dragon". Many fans rejected "The Eyes of the Dragon" because it was an epic fantasy book, with virtually none of the horror that initially made his reputation. Paul Sheldon feeling chained to the "Misery" books by his fans was a metaphor for King's feeling chained to horror fiction. Another source was King's addiction to drugs and alcohol, and his struggle to get sober. He stated: "Take the psychotic nurse in "Misery", which I wrote when I was having such a tough time with dope. I knew what I was writing about. There was never any question. Annie was my drug problem, and she was my number-one fan. God, she never wanted to leave."


title: Misery (novel)

text: When further addressing the idea of whether the character of Paul Sheldon was based on himself, King stated that in certain ways, he was, but in the ways where every character is a part of the author in some way: "It would be fair enough to ask, I suppose, if Paul Sheldon in "Misery" is me. Certain "parts" of him are ... but I think you will find that, if you continue to write fiction, every character you create is partly you."


title: Misery (novel)

text: King has also attributed a dream he had while on a trans-Atlantic flight to London with the situation and characters that became fleshed out in "Misery". He noted that he wrote the idea on an American Airlines cocktail napkin when he woke up so he could make sure to remember it, writing: "She speaks earnestly but never quite makes eye contact. A big woman and solid all through; she is an absence of hiatus. 'I wasn't trying to be funny in a mean way when I named my pig Misery, no sir. Please don't think that. No, I named her in the spirit of fan love, which is the purest love there is. You should be flattered.'"


title: Misery (novel)

text: King and his wife, Tabitha King, stayed in London's Brown's Hotel, where he wrote "sixteen pages of a steno notebook"; the concierge let him work at a desk once owned by Rudyard Kipling, who had died of a stroke while using it. King thought that the book would only be around 30,000 words, but it ended up being almost four times that at 370 pages. Its working title was "The Annie Wilkes Edition". While discussing the pros and cons (mostly cons) of pre-plotting novels, King mentioned that he had originally planned for Annie to force her prisoner to write a book, which she would then bind in Paul's skin. When commenting on why he chose not to go that route, King said:


title: Misery (novel)

text: The novel was adapted into a film in 1990, directed by Rob Reiner and scripted by William Goldman. James Caan and Kathy Bates starred as Paul Sheldon and Annie Wilkes, with Lauren Bacall, Richard Farnsworth and Frances Sternhagen in supporting roles. The film was a critical and commercial success, and continues to be ranked as one of the best Stephen King adaptations. For her performance as Annie Wilkes, Kathy Bates won the 1991 Academy Award for Best Actress - one of the few Oscar wins for a performance in the horror genre, and the first for any King adaptation - and was launched into mainstream stardom. In June 2003, the American Film Institute included Annie Wilkes, as played by Bates, in their "100 Heroes and Villains" list, ranking her as the 17th most iconic villain (and sixth most iconic villainess) in the history of film.


title: Misery (novel)

text: A version of Annie Wilkes, portrayed by Lizzy Caplan, is the main character of the second season of "Castle Rock". The season finale concludes with Annie attending a book signing for a "Misery" novel by Paul Sheldon.


title: Misery (novel)

text: The novel was also adapted into a play by Simon Moore. The play premiered in London at the Criterion Theater in December 1992, starring Sharon Gless and Bill Paterson and directed by Moore. The play, directed by Alan Cohen, was revived in 2005 at the Kings Head Theatre in London, starring Michael Praed and Susan Penhaligon.


title: Misery (novel)

text: In 2014, Dutch composer and theater producer Florus van Rooijen adapted the novel into a "feel bad" musical.


title: Misery (novel)

text: A different play written by William Goldman (who also wrote the film's screenplay) and directed by Will Frears opened on Broadway in 2015 for a limited engagement. The play starred Bruce Willis as Paul Sheldon and Laurie Metcalf as Annie Wilkes. It opened in October 2015 and closed on February 16, 2016. For her performance as Wilkes, Metcalf was nominated for a Tony Award for Best Actress in a Play. The play was originally premiered in 2012 at Bucks County Playhouse before moving to Broadway. This new version is not connected to the earlier adaptation by Simon Moore.


title: Misery (novel)

text: In October 2019, a Finnish play adaptation of "Misery" called "Piina" was performed at the Tampere Theatre in Tampere, Finland. The play was directed by Antti Mikkola and starring Esa Latva-Äijö as Paul Sheldon and Mari Turunen as Annie Wilkes. Also in September of the same year, Kuopio City Theatre in Kuopio, Finland presented another interpretation under the name "Piina", directed by Olli-Matti Oinonen and starring Seppo Pääkkönen as Paul Sheldon and Henna Haverinen as Annie Wilkes. Both adaptations (based on the Goldman screenplay) were well-received by the audience and critics. and in Pori Porin Teatteri in November 2022 directed by Tuomo Aitta and starring Vesa Haltsonen as Paul Sheldon and Mirva Tolppanen as Annie Wilkes.


title: Misery (novel)

text: Moore's stage adaptation was itself adapted for radio and broadcast on the BBC World Service. The program was produced by Dirk Maggs, directed by Marion Nancarrow and starred Nicholas Farrell as Paul Sheldon and Miriam Margolyes as Annie Wilkes. The program was later released on CD by the BBC.


title: Christian Kane

text: Christian Kane (born Christopher Michael Short) is an American actor and singer-songwriter. He is known for his roles in the television shows "Angel", "Leverage", "The Librarians", and "Into the West", and the movies "Just Married", "Taxi", and "Secondhand Lions".


title: Christian Kane

text: Kane is the lead singer of the country-southern rock band Kane. On December 7, 2010, they released "The House Rules", their third album and their debut for record label Bigger Picture Music Group. The album reached no. 25 on the "Billboard" Country Albums chart. The first single from the album, also titled "The House Rules", debuted at no. 54 on the "Billboard" Country Songs chart. The second single, “Let Me Go”, was released on July 11, 2011.


title: Christian Kane

text: Kane has stated that he is of Cherokee (Native American) ancestry. His parents participated in, and met at, the rodeo. The family moved around the South and the Midwest because his father was in the oil business, and they finally settled in Norman, Oklahoma, when Kane was in eighth grade. While growing up in Texas and Oklahoma, Kane was a collegiate-style wrestler and played football (as a strong safety). He studied art history at the University of Oklahoma, but decided he wanted to be an actor and headed to Los Angeles before finishing the degree. In Los Angeles, he worked at a talent management company, where he delivered scripts in exchange for getting acting jobs.


title: Christian Kane

text: Kane landed his first acting role in 1997 as one of the leads in MGM's television series "Fame L.A." playing a country singer who moved to Los Angeles from Kansas. His television roles have included a recurring role in Joss Whedon’s "Angel" as the lawyer Lindsey MacDonald, the Jerry Bruckheimer-produced series "Close to Home" on CBS, the TNT television film "Crossfire Trail" in which he appeared alongside Tom Selleck, and the role of Abe Wheeler in the Steven Spielberg-produced 2005 miniseries "Into the West". He starred as Billy Ryan in the MTV movie "Love Song" in 2000, alongside R&B artist Monica.


title: Christian Kane

text: Kane’s appearances on the big screen include the 20th Century Fox film "Just Married" and New Line Cinema's "Secondhand Lions" (as the younger version of Robert Duvall's Hub McCann, he has a scar on his upper lip from an injury he received while filming the movie). He also appeared in "Taxi", "Life or Something Like It", the Peter Berg-directed "Friday Night Lights", and the Warner Bros. baseball film "Summer Catch".


title: Christian Kane

text: In 2007, Kane was featured in the Carrie Underwood music video "So Small", playing the role of one of the three converging stories. In 2009, he appeared in the psychological thriller, "Hide", in which he played the lead role of Billy, and "The Donner Party" which is based on the true story of the Donner Party. In 2010, he starred in the romantic drama, "Not Since You".


title: Christian Kane

text: From 2008 to 2012, Kane appeared on the TNT television series "Leverage" as Eliot Spencer, a retrieval specialist and black ops soldier who teams up with four other specialists to undo the injustices perpetrated upon the helpless. Kane performed all his own fight scenes and also choreographed fights for the series. Kane plays the same character in "", which premiered in July 2021, streaming on IMDb TV. The show takes up the team's adventures 8 years after the last episode.


title: Christian Kane

text: In 2013, Kane appeared as JT Maxwell, brother to Rebecca Romijn's female lead Michelle Maxwell on TNT's "King & Maxwell". He appeared again with Romijn. co-starring in the 2014 to 2018 TNT television series "The Librarians", based on "The Librarian" film series.


title: Christian Kane

text: In 2020, Kane starred as Alex Walker on the drama series Almost Paradise. In an interview with Tell-Tale TV, Kane described that character as being several of his previous roles on other series rolled into one.


title: Christian Kane

text: In 1997, Kane met Steve Carlson, who had taken over his old job. They started writing songs together, and in 1998 formed the Southern rock band Kane. They have toured the U.S., as well as England and Germany. The band has self-released two albums, their self-titled debut, "Kane", in 2002, and a recording of a live acoustic set, "Acoustic Live In London!" in 2004.


title: Christian Kane

text: The band consists of Kane (lead vocals, guitar), Carlson (rhythm guitar, backing vocals), Jason Southard (lead guitar), Will Amend (bass guitar), and Ryan Baker (drums) and is signed to independent record label Bigger Picture Music Group. Their label debut, "The House Rules", was released December 7, 2010. It debuted at no. 1 on the "Billboard" Heatseekers album chart and no. 25 on the Country Albums chart. The album was produced by Bob Ezrin and Jimmie Lee Sloas.


title: Christian Kane

text: The first single from the album, also titled "The House Rules", debuted at no. 54 on the "Billboard" Country Songs chart and was the seventh-most added song on Mediabase Country stations on its official impact date. The video for the single was directed by Timothy Hutton and premiered on CMT's "Big New Music Weekend" October 1, 2010. "The House Rules" was featured in the video game "NASCAR 09". The second single, "Let Me Go", was released on July 11, 2011. The video for the single, directed by Roman White, premiered on CMT August 8, 2011 and reached no. 1 on their Today's Top Videos chart .


title: Christian Kane

text: Kane is also signed to a songwriting deal with EMI Music Publishing and writes much of his own material. Trace Adkins released a song written by Kane called "Happy Man" on his 2010 album, "Cowboy's Back in Town".


title: Christian Kane

text: Kane's co-writing efforts include songs written with Blair Daly, Brett James, David Lee Murphy, Casey Beathard, and Jerrod Niemann. "Thinking of You", a song he co-wrote with Blair Daly, was featured in "Leverage" Season 3 episode, "The Studio Job."


title: Viperidae

text: The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, and various other isolated islands. They are venomous and have long (relative to non-vipers), hinged fangs that permit deep penetration and injection of their venom. Four subfamilies are currently recognized. They are also known as viperids. The name "viper" is derived from the Latin word "vipera", -"ae", also meaning viper, possibly from "vivus" ("living") and "parere" ("to beget"), referring to the trait viviparity (giving live birth) common in vipers like most of the species of Boidae.


title: Viperidae

text: All viperids have a pair of relatively long solenoglyphous (hollow) fangs that are used to inject venom from glands located towards the rear of the upper jaws, just behind the eyes. Each of the two fangs is at the front of the mouth on a short maxillary bone that can rotate back and forth. When not in use, the fangs fold back against the roof of the mouth and are enclosed in a membranous sheath. This rotating mechanism allows for very long fangs to be contained in a relatively small mouth. The left and right fangs can be rotated together or independently. During a strike, the mouth can open nearly 180° and the maxilla rotates forward, erecting the fangs as late as possible so that the fangs do not become damaged, as they are brittle. The jaws close upon impact and the muscular sheaths encapsulating the venom glands contract, injecting the venom as the fangs penetrate the target. This action is very fast; in defensive strikes, it will be more a stab than a bite. Viperids use this mechanism primarily for immobilization and digestion of prey. Pre-digestion occurs as the venom contains proteases, which degrade tissues. Secondarily, it is used for self defense, though in cases with nonprey, such as humans, they may give a dry bite (not inject any venom). A dry bite allows the snake to conserve its precious reserve of venom, because once it has been depleted, time is needed to replenish it, leaving the snake vulnerable. In addition to being able to deliver dry bites, vipers can inject larger quantities of venom into larger prey targets, and smaller amounts into small prey. This causes the ideal amount of predigestion for the lowest amount of venom.


title: Viperidae

text: Almost all vipers have keeled scales, a stocky build with a short tail, and a triangle-shaped head distinct from the neck, owing to the location of the venom glands. The great majority have vertically elliptical, or slit-shaped, pupils that can open wide to cover most of the eye or close almost completely, which helps them to see in a wide range of light levels. Typically, vipers are nocturnal and ambush their prey.


title: Viperidae

text: Compared to many other snakes, vipers often appear rather sluggish. Most are ovoviviparous: the eggs are retained inside the mother's body, and the young emerge living. However, a few lay eggs in nests. Typically, the number of young in a clutch remains constant, but as the weight of the mother increases, larger eggs are produced, yielding larger young.


title: Viperidae

text: Viperid snakes are found in the Americas, Africa, Eurasia, and South Asia. In the Americas, they are native from south of 48°N. In the Old World, viperids are located everywhere except Siberia, Ireland, and north of the Arctic Circle in Norway and Sweden. Wild viperids are not found in Australia. The common adder, a viperid, is the only venomous snake found in Great Britain.


title: Viperidae

text: Viperid venoms typically contain an abundance of protein-degrading enzymes, called proteases, that produce symptoms such as pain, strong local swelling and necrosis, blood loss from cardiovascular damage complicated by coagulopathy, and disruption of the blood-clotting system. Also being vasculotoxic in nature, viperine venom causes vascular endothelial damage and hemolysis. Death is usually caused by collapse in blood pressure. This is in contrast to elapid venoms, which generally contain neurotoxins that disable muscle contraction and cause paralysis. Death from elapid bites usually results from asphyxiation because the diaphragm can no longer contract, but this rule does not always apply; some elapid bites include proteolytic symptoms typical of viperid bites, while some viperid bites produce neurotoxic symptoms.


title: Viperidae

text: Proteolytic venom is also dual-purpose: first, it is used for defense and to immobilize prey, as with neurotoxic venoms; second, many of the venom's enzymes have a digestive function, breaking down molecules such as lipids, nucleic acids, and proteins. This is an important adaptation, as many vipers have inefficient digestive systems.


title: Viperidae

text: Due to the nature of proteolytic venom, a viperid bite is often a very painful experience and should always be taken seriously, though it may not necessarily prove fatal. Even with prompt and proper treatment, a bite can still result in a permanent scar, and in the worst cases, the affected limb may even have to be amputated. A victim's fate is impossible to predict, as this depends on many factors, including the species and size of the snake involved, how much venom was injected (if any), and the size and condition of the patient before being bitten. Viper bite victims may also be allergic to the venom or the antivenom.


title: Viperidae

text: These snakes can decide how much venom to inject depending on the circumstances. The most important determinant of venom expenditure is generally the size of the snake; larger specimens can deliver much more venom. The species is also important, since some are likely to inject more venom than others, may have more venom available, strike more accurately, or deliver a number of bites in a short time. In predatory bites, factors that influence the amount of venom injected include the size of the prey, the species of prey, and whether the prey item is held or released. The need to label prey for chemosensory relocation after a bite and release may also play a role. In defensive bites, the amount of venom injected may be determined by the size or species of the predator (or antagonist), as well as the assessed level of threat, although larger assailants and higher threat levels may not necessarily lead to larger amounts of venom being injected.


title: Viperidae

text: Hemotoxic venom takes more time than neurotoxic venom to immobilize prey, so viperid snakes need to track down prey animals after they have been bitten, in a process known as "prey relocalization". Vipers are able to do this via certain proteins contained in their venom. This important adaptation allowed rattlesnakes to evolve the strike-and-release bite mechanism, which provided a huge benefit to snakes by minimizing contact with potentially dangerous prey animals. This adaptation, then, requires the snake to track down the bitten animal to eat it, in an environment full of other animals of the same species. Western diamondback rattlesnakes respond more actively to mouse carcasses that have been injected with crude rattlesnake venom. When the various components of the venom were separated out, the snakes responded to mice injected with two kinds of disintegrins, which are responsible for allowing the snakes to track down their prey.


title: Viperidae

text: Pit vipers have specialized sensory organs near the nostrils called heat-sensing pits. The location of this organ is unique to pit vipers. These pits have the ability to detect thermal radiation emitted by warm-blooded animals, helping them better understand their environment. Internally the organ forms a small pit lined with membranes, external and internal, attached to the trigeminal nerve. Infrared light signals the internal membranes, which in turn signal the trigeminal nerve and send the infrared signals to the brain, where they are overlaid onto the visual image created by the eyes.


title: Viperidae

text: Whether family Viperidae is attributed to Oppel (1811), as opposed to Laurenti (1768) or Gray (1825), is subject to some interpretation. The consensus among leading experts, though, is that Laurenti used "viperae" as the plural of "vipera" (Latin for "viper", "adder", or "snake") and did not intend for it to indicate a family group taxon. Rather, it is attributed to Oppel, based on his Viperini as a distinct family group name, despite the fact that Gray was the first to use the form Viperinae.


title: Ibn al-Haytham

text: Ḥasan Ibn al-Haytham, Latinized as Alhazen (; full name ; ), was a medieval mathematician, astronomer, and physicist of the Islamic Golden Age from present-day Iraq. Referred to as "the father of modern optics", he made significant contributions to the principles of optics and visual perception in particular. His most influential work is titled "Kitāb al-Manāẓir" (Arabic: , "Book of Optics"), written during 1011–1021, which survived in a Latin edition.


title: Ibn al-Haytham

text: Ibn al-Haytham was an early proponent of the concept that a hypothesis must be supported by experiments based on confirmable procedures or mathematical evidence—an early pioneer in the scientific method five centuries before Renaissance scientists. On account of this, he is sometimes described as the world's "first true scientist". He was also a polymath, writing on philosophy, theology and medicine. Ibn al-Haytham was the first to explain that vision occurs when light reflects from an object and then passes to one's eyes, and to argue that vision occurs in the brain, pointing to observations that it is subjective and affected by personal experience.


title: Ibn al-Haytham

text: Born in Basra, he spent most of his productive period in the Fatimid capital of Cairo and earned his living authoring various treatises and tutoring members of the nobilities. Ibn al-Haytham is sometimes given the byname "al-Baṣrī" after his birthplace, or "al-Miṣrī" ("the Egyptian"). Al-Haytham was dubbed the "Second Ptolemy" by Abu'l-Hasan Bayhaqi and "The Physicist" by John Peckham. Ibn al-Haytham paved the way for the modern science of physical optics.


title: Ibn al-Haytham

text: Ibn al-Haytham (Alhazen) was born c. 965 to a family of Arab or Persian origin in Basra, Iraq, which was at the time part of the Buyid emirate. His initial influences were in the study of religion and service to the community. At the time, society had a number of conflicting views of religion that he ultimately sought to step aside from religion. This led to him delving into the study of mathematics and science. He held a position with the title "vizier" in his native Basra, and made a name for himself on his knowledge of applied mathematics. As he claimed to be able to regulate the flooding of the Nile, he was invited to meet the Fatimid Caliph al-Hakim in order to realise a hydraulic project at Aswan. However, Ibn al-Haytham was forced to concede the impracticability of his project.


title: Ibn al-Haytham

text: Upon his return to Cairo, he was given an administrative post. After he proved unable to fulfill this task as well, he contracted the ire of the caliph al-Hakim, and is said to have been forced into hiding until the caliph's death in 1021, after which his confiscated possessions were returned to him.


title: Ibn al-Haytham

text: Legend has it that Alhazen feigned madness and was kept under house arrest during this period. During this time, he wrote his influential "Book of Optics". Alhazen continued to live in Cairo, in the neighborhood of the famous University of al-Azhar, and lived from the proceeds of his literary production until his death in c. 1040. (A copy of Apollonius' "Conics", written in Ibn al-Haytham's own handwriting exists in Aya Sofya: (MS Aya Sofya 2762, 307 fob., dated Safar 415 A.H. [1024]).)


title: Ibn al-Haytham

text: Among his students were Sorkhab (Sohrab), a Persian from Semnan, and Abu al-Wafa Mubashir ibn Fatek, an Egyptian prince.


title: Ibn al-Haytham

text: Alhazen's most famous work is his seven-volume treatise on optics "Kitab al-Manazir" ("Book of Optics"), written from 1011 to 1021. In it, Ibn al-Haytham was the first to explain that vision occurs when light reflects from an object and then passes to one's eyes, and to argue that vision occurs in the brain, pointing to observations that it is subjective and affected by personal experience.


title: Ibn al-Haytham

text: "Optics" was translated into Latin by an unknown scholar at the end of the 12th century or the beginning of the 13th century.


title: Ibn al-Haytham

text: This work enjoyed a great reputation during the Middle Ages. The Latin version of "De aspectibus" was translated at the end of the 14th century into Italian vernacular, under the title "De li aspecti".


title: Ibn al-Haytham

text: It was printed by Friedrich Risner in 1572, with the title "Opticae thesaurus: Alhazeni Arabis libri septem, nuncprimum editi; Eiusdem liber De Crepusculis et nubium ascensionibus" (English: Treasury of Optics: seven books by the Arab Alhazen, first edition; by the same, on twilight and the height of clouds).


title: Ibn al-Haytham

text: Risner is also the author of the name variant "Alhazen"; before Risner he was known in the west as Alhacen.


title: Ibn al-Haytham

text: Works by Alhazen on geometric subjects were discovered in the Bibliothèque nationale in Paris in 1834 by E. A. Sedillot. In all, A. Mark Smith has accounted for 18 full or near-complete manuscripts, and five fragments, which are preserved in 14 locations, including one in the Bodleian Library at Oxford, and one in the library of Bruges.


title: Ibn al-Haytham

text: Two major theories on vision prevailed in classical antiquity. The first theory, the emission theory, was supported by such thinkers as Euclid and Ptolemy, who believed that sight worked by the eye emitting rays of light. The second theory, the intromission theory supported by Aristotle and his followers, had physical forms entering the eye from an object. Previous Islamic writers (such as al-Kindi) had argued essentially on Euclidean, Galenist, or Aristotelian lines. The strongest influence on the "Book of Optics" was from Ptolemy's "Optics", while the description of the anatomy and physiology of the eye was based on Galen's account. Alhazen's achievement was to come up with a theory that successfully combined parts of the mathematical ray arguments of Euclid, the medical tradition of Galen, and the intromission theories of Aristotle. Alhazen's intromission theory followed al-Kindi (and broke with Aristotle) in asserting that "from each point of every colored body, illuminated by any light, issue light and color along every straight line that can be drawn from that point". This left him with the problem of explaining how a coherent image was formed from many independent sources of radiation; in particular, every point of an object would send rays to every point on the eye.


title: Ibn al-Haytham

text: What Alhazen needed was for each point on an object to correspond to one point only on the eye. He attempted to resolve this by asserting that the eye would only perceive perpendicular rays from the object—for any one point on the eye, only the ray that reached it directly, without being refracted by any other part of the eye, would be perceived. He argued, using a physical analogy, that perpendicular rays were stronger than oblique rays: in the same way that a ball thrown directly at a board might break the board, whereas a ball thrown obliquely at the board would glance off, perpendicular rays were stronger than refracted rays, and it was only perpendicular rays which were perceived by the eye. As there was only one perpendicular ray that would enter the eye at any one point, and all these rays would converge on the centre of the eye in a cone, this allowed him to resolve the problem of each point on an object sending many rays to the eye; if only the perpendicular ray mattered, then he had a one-to-one correspondence and the confusion could be resolved. He later asserted (in book seven of the "Optics") that other rays would be refracted through the eye and perceived "as if" perpendicular. His arguments regarding perpendicular rays do not clearly explain why "only" perpendicular rays were perceived; why would the weaker oblique rays not be perceived more weakly? His later argument that refracted rays would be perceived as if perpendicular does not seem persuasive. However, despite its weaknesses, no other theory of the time was so comprehensive, and it was enormously influential, particularly in Western Europe. Directly or indirectly, his "De Aspectibus" (Book of Optics) inspired much activity in optics between the 13th and 17th centuries. Kepler's later theory of the retinal image (which resolved the problem of the correspondence of points on an object and points in the eye) built directly on the conceptual framework of Alhazen.


title: Ibn al-Haytham

text: Although only one commentary on Alhazen's optics has survived the Islamic Middle Ages, Geoffrey Chaucer mentions the work in "The Canterbury Tales":


title: Ibn al-Haytham

text: Ibn al-Haytham was known for his contributions to Optics specifically thereof vision and theory of light. He assumed ray of light was radiated from specific points on the surface. Possibility of light propagation suggest that light was independent of vision. Light also moves at a very fast speed.


title: Ibn al-Haytham

text: Alhazen showed through experiment that light travels in straight lines, and carried out various experiments with lenses, mirrors, refraction, and reflection. His analyses of reflection and refraction considered the vertical and horizontal components of light rays separately.


title: Ibn al-Haytham

text: Alhazen studied the process of sight, the structure of the eye, image formation in the eye, and the visual system. Ian P. Howard argued in a 1996 "Perception" article that Alhazen should be credited with many discoveries and theories previously attributed to Western Europeans writing centuries later. For example, he described what became in the 19th century Hering's law of equal innervation. He wrote a description of vertical horopters 600 years before Aguilonius that is actually closer to the modern definition than Aguilonius's—and his work on binocular disparity was repeated by Panum in 1858. Craig Aaen-Stockdale, while agreeing that Alhazen should be credited with many advances, has expressed some caution, especially when considering Alhazen in isolation from Ptolemy, with whom Alhazen was extremely familiar. Alhazen corrected a significant error of Ptolemy regarding binocular vision, but otherwise his account is very similar; Ptolemy also attempted to explain what is now called Hering's law. In general, Alhazen built on and expanded the optics of Ptolemy.


title: Ibn al-Haytham

text: In a more detailed account of Ibn al-Haytham's contribution to the study of binocular vision based on Lejeune and Sabra, Raynaud showed that the concepts of correspondence, homonymous and crossed diplopia were in place in Ibn al-Haytham's optics. But contrary to Howard, he explained why Ibn al-Haytham did not give the circular figure of the horopter and why, by reasoning experimentally, he was in fact closer to the discovery of Panum's fusional area than that of the Vieth-Müller circle. In this regard, Ibn al-Haytham's theory of binocular vision faced two main limits: the lack of recognition of the role of the retina, and obviously the lack of an experimental investigation of ocular tracts.


title: Ibn al-Haytham

text: Alhazen's most original contribution was that, after describing how he thought the eye was anatomically constructed, he went on to consider how this anatomy would behave functionally as an optical system. His understanding of pinhole projection from his experiments appears to have influenced his consideration of image inversion in the eye, which he sought to avoid. He maintained that the rays that fell perpendicularly on the lens (or glacial humor as he called it) were further refracted outward as they left the glacial humor and the resulting image thus passed upright into the optic nerve at the back of the eye. He followed Galen in believing that the lens was the receptive organ of sight, although some of his work hints that he thought the retina was also involved.


title: Ibn al-Haytham

text: Alhazen's synthesis of light and vision adhered to the Aristotelian scheme, exhaustively describing the process of vision in a logical, complete fashion.


title: Ibn al-Haytham

text: An aspect associated with Alhazen's optical research is related to systemic and methodological reliance on experimentation ("i'tibar")(Arabic: إعتبار) and controlled testing in his scientific inquiries. Moreover, his experimental directives rested on combining classical physics ("ilm tabi'i") with mathematics ("ta'alim"; geometry in particular). This mathematical-physical approach to experimental science supported most of his propositions in "Kitab al-Manazir" ("The Optics"; "De aspectibus" or "Perspectivae") and grounded his theories of vision, light and colour, as well as his research in catoptrics and dioptrics (the study of the reflection and refraction of light, respectively).


title: Ibn al-Haytham

text: According to Matthias Schramm, Alhazen "was the first to make a systematic use of the method of varying the experimental conditions in a constant and uniform manner, in an experiment showing that the intensity of the light-spot formed by the projection of the moonlight through two small apertures onto a screen diminishes constantly as one of the apertures is gradually blocked up." G. J. Toomer expressed some skepticism regarding Schramm's view, partly because at the time (1964) the "Book of Optics" had not yet been fully translated from Arabic, and Toomer was concerned that without context, specific passages might be read anachronistically. While acknowledging Alhazen's importance in developing experimental techniques, Toomer argued that Alhazen should not be considered in isolation from other Islamic and ancient thinkers. Toomer concluded his review by saying that it would not be possible to assess Schramm's claim that Ibn al-Haytham was the true founder of modern physics without translating more of Alhazen's work and fully investigating his influence on later medieval writers.


title: Ibn al-Haytham

text: His work on catoptrics in Book V of the Book of Optics contains a discussion of what is now known as Alhazen's problem, first formulated by Ptolemy in 150 AD. It comprises drawing lines from two points in the plane of a circle meeting at a point on the circumference and making equal angles with the normal at that point. This is equivalent to finding the point on the edge of a circular billiard table at which a player must aim a cue ball at a given point to make it bounce off the table edge and hit another ball at a second given point. Thus, its main application in optics is to solve the problem, "Given a light source and a spherical mirror, find the point on the mirror where the light will be reflected to the eye of an observer." This leads to an equation of the fourth degree. This eventually led Alhazen to derive a formula for the sum of fourth powers, where previously only the formulas for the sums of squares and cubes had been stated. His method can be readily generalized to find the formula for the sum of any integral powers, although he did not himself do this (perhaps because he only needed the fourth power to calculate the volume of the paraboloid he was interested in). He used his result on sums of integral powers to perform what would now be called an integration, where the formulas for the sums of integral squares and fourth powers allowed him to calculate the volume of a paraboloid. Alhazen eventually solved the problem using conic sections and a geometric proof. His solution was extremely long and complicated and may not have been understood by mathematicians reading him in Latin translation.


title: Ibn al-Haytham

text: Later mathematicians used Descartes' analytical methods to analyse the problem. An algebraic solution to the problem was finally found in 1965 by Jack M. Elkin, an actuarian. Other solutions were discovered in 1989, by Harald Riede and in 1997 by the Oxford mathematician Peter M. Neumann.


title: Ibn al-Haytham

text: Recently, Mitsubishi Electric Research Laboratories (MERL) researchers solved the extension of Alhazen's problem to general rotationally symmetric quadric mirrors including hyperbolic, parabolic and elliptical mirrors.


title: Ibn al-Haytham

text: The camera obscura was known to the ancient Chinese, and was described by the Han Chinese polymath Shen Kuo in his scientific book "Dream Pool Essays", published in the year 1088 C.E. Aristotle had discussed the basic principle behind it in his "Problems", but Alhazen's work also contained the first clear description, outside of China, of camera obscura in the areas of the Middle East, Europe, Africa and India. and early analysis of the device.


title: Ibn al-Haytham

text: In his essay, Ibn al-Haytham writes that he observed the sickle-like shape of the sun at the time of an eclipse. The introduction reads as follows: "The image of the sun at the time of the eclipse, unless it is total, demonstrates that when its light passes through a narrow, round hole and is cast on a plane opposite to the hole it takes on the form of a moonsickle."


title: Ibn al-Haytham

text: It is admitted that his findings solidified the importance in the history of the camera obscura but this treatise is important in many other respects.


title: Ibn al-Haytham

text: Ancient optics and medieval optics were divided into optics and burning mirrors. Optics proper mainly focused on the study of vision, while burning mirrors focused on the properties of light and luminous rays. "On the shape of the eclipse" is probably one of the first attempts made by Ibn al-Haytham to articulate these two sciences.


title: Ibn al-Haytham

text: Very often Ibn al-Haytham's discoveries benefited from the intersection of mathematical and experimental contributions. This is the case with "On the shape of the eclipse". Besides the fact that this treatise allowed more people to study partial eclipses of the sun, it especially allowed to better understand how the camera obscura works. This treatise is a physico-mathematical study of image formation inside the camera obscura. Ibn al-Haytham takes an experimental approach, and determines the result by varying the size and the shape of the aperture, the focal length of the camera, the shape and intensity of the light source.


title: Ibn al-Haytham

text: In his work he explains the inversion of the image in the camera obscura, the fact that the image is similar to the source when the hole is small, but also the fact that the image can differ from the source when the hole is large. All these results are produced by using a point analysis of the image.


title: Ibn al-Haytham

text: The "Kitab al-Manazir" (Book of Optics) describes several experimental observations that Alhazen made and how he used his results to explain certain optical phenomena using mechanical analogies. He conducted experiments with projectiles and concluded that only the impact of perpendicular projectiles on surfaces was forceful enough to make them penetrate, whereas surfaces tended to deflect oblique projectile strikes. For example, to explain refraction from a rare to a dense medium, he used the mechanical analogy of an iron ball thrown at a thin slate covering a wide hole in a metal sheet. A perpendicular throw breaks the slate and passes through, whereas an oblique one with equal force and from an equal distance does not. He also used this result to explain how intense, direct light hurts the eye, using a mechanical analogy: Alhazen associated 'strong' lights with perpendicular rays and 'weak' lights with oblique ones. The obvious answer to the problem of multiple rays and the eye was in the choice of the perpendicular ray, since only one such ray from each point on the surface of the object could penetrate the eye.


title: Ibn al-Haytham

text: Sudanese psychologist Omar Khaleefa has argued that Alhazen should be considered the founder of experimental psychology, for his pioneering work on the psychology of visual perception and optical illusions. Khaleefa has also argued that Alhazen should also be considered the "founder of psychophysics", a sub-discipline and precursor to modern psychology. Although Alhazen made many subjective reports regarding vision, there is no evidence that he used quantitative psychophysical techniques and the claim has been rebuffed.


title: Ibn al-Haytham

text: Alhazen offered an explanation of the Moon illusion, an illusion that played an important role in the scientific tradition of medieval Europe. Many authors repeated explanations that attempted to solve the problem of the Moon appearing larger near the horizon than it does when higher up in the sky. Alhazen argued against Ptolemy's refraction theory, and defined the problem in terms of perceived, rather than real, enlargement. He said that judging the distance of an object depends on there being an uninterrupted sequence of intervening bodies between the object and the observer. When the Moon is high in the sky there are no intervening objects, so the Moon appears close. The perceived size of an object of constant angular size varies with its perceived distance. Therefore, the Moon appears closer and smaller high in the sky, and further and larger on the horizon. Through works by Roger Bacon, John Pecham and Witelo based on Alhazen's explanation, the Moon illusion gradually came to be accepted as a psychological phenomenon, with the refraction theory being rejected in the 17th century. Although Alhazen is often credited with the perceived distance explanation, he was not the first author to offer it. Cleomedes ( 2nd century) gave this account (in addition to refraction), and he credited it to Posidonius ( 135–50 BCE). Ptolemy may also have offered this explanation in his "Optics", but the text is obscure. Alhazen's writings were more widely available in the Middle Ages than those of these earlier authors, and that probably explains why Alhazen received the credit.


title: Ibn al-Haytham

text: Besides the "Book of Optics", Alhazen wrote several other treatises on the same subject, including his "Risala fi l-Daw"' ("Treatise on Light"). He investigated the properties of luminance, the rainbow, eclipses, twilight, and moonlight. Experiments with mirrors and the refractive interfaces between air, water, and glass cubes, hemispheres, and quarter-spheres provided the foundation for his theories on catoptrics.


title: Ibn al-Haytham

text: Alhazen discussed the physics of the celestial region in his "Epitome of Astronomy", arguing that Ptolemaic models must be understood in terms of physical objects rather than abstract hypotheses—in other words that it should be possible to create physical models where (for example) none of the celestial bodies would collide with each other. The suggestion of mechanical models for the Earth centred Ptolemaic model "greatly contributed to the eventual triumph of the Ptolemaic system among the Christians of the West". Alhazen's determination to root astronomy in the realm of physical objects was important, however, because it meant astronomical hypotheses "were accountable to the laws of physics", and could be criticised and improved upon in those terms.


title: Ibn al-Haytham

text: In his work, Alhazen discussed theories on the motion of a body. In his "Treatise on Place", Alhazen disagreed with Aristotle's view that nature abhors a void, and he used geometry in an attempt to demonstrate that place ("al-makan") is the imagined three-dimensional void between the inner surfaces of a containing body.


title: Ibn al-Haytham

text: In his "On the Configuration of the World" Alhazen presented a detailed description of the physical structure of the earth:


title: Ibn al-Haytham

text: The book is a non-technical explanation of Ptolemy's "Almagest", which was eventually translated into Hebrew and Latin in the 13th and 14th centuries and subsequently had an influence on astronomers such as Georg von Peuerbach during the European Middle Ages and Renaissance.


title: Ibn al-Haytham

text: In his "Al-Shukūk ‛alā Batlamyūs", variously translated as "Doubts Concerning Ptolemy" or "Aporias against Ptolemy", published at some time between 1025 and 1028, Alhazen criticized Ptolemy's "Almagest", "Planetary Hypotheses", and "Optics", pointing out various contradictions he found in these works, particularly in astronomy. Ptolemy's "Almagest" concerned mathematical theories regarding the motion of the planets, whereas the "Hypotheses" concerned what Ptolemy thought was the actual configuration of the planets. Ptolemy himself acknowledged that his theories and configurations did not always agree with each other, arguing that this was not a problem provided it did not result in noticeable error, but Alhazen was particularly scathing in his criticism of the inherent contradictions in Ptolemy's works. He considered that some of the mathematical devices Ptolemy introduced into astronomy, especially the equant, failed to satisfy the physical requirement of uniform circular motion, and noted the absurdity of relating actual physical motions to imaginary mathematical points, lines and circles:


title: Ibn al-Haytham

text: Having pointed out the problems, Alhazen appears to have intended to resolve the contradictions he pointed out in Ptolemy in a later work. Alhazen believed there was a "true configuration" of the planets that Ptolemy had failed to grasp. He intended to complete and repair Ptolemy's system, not to replace it completely. In the "Doubts Concerning Ptolemy" Alhazen set out his views on the difficulty of attaining scientific knowledge and the need to question existing authorities and theories:


title: Ibn al-Haytham

text: He held that the criticism of existing theories—which dominated this book—holds a special place in the growth of scientific knowledge.


title: Ibn al-Haytham

text: Alhazen's "The Model of the Motions of Each of the Seven Planets" was written 1038. Only one damaged manuscript has been found, with only the introduction and the first section, on the theory of planetary motion, surviving. (There was also a second section on astronomical calculation, and a third section, on astronomical instruments.) Following on from his "Doubts on Ptolemy", Alhazen described a new, geometry-based planetary model, describing the motions of the planets in terms of spherical geometry, infinitesimal geometry and trigonometry. He kept a geocentric universe and assumed that celestial motions are uniformly circular, which required the inclusion of epicycles to explain observed motion, but he managed to eliminate Ptolemy's equant. In general, his model didn't try to provide a causal explanation of the motions, but concentrated on providing a complete, geometric description that could explain observed motions without the contradictions inherent in Ptolemy's model.


title: Ibn al-Haytham

text: Alhazen wrote a total of twenty-five astronomical works, some concerning technical issues such as "Exact Determination of the Meridian", a second group concerning accurate astronomical observation, a third group concerning various astronomical problems and questions such as the location of the Milky Way; Alhazen made the first systematic effort of evaluating the Milky Way's parallax, combining Ptolemy's data and his own. He concluded that the parallax is (probably very much) smaller than Lunar parallax, and the Milky way should be a celestial object. Though he was not the first who argued that the Milky Way does not belong to the atmosphere, he is the first who did quantitative analysis for the claim.


title: Ibn al-Haytham

text: The fourth group consists of ten works on astronomical theory, including the "Doubts" and "Model of the Motions" discussed above.


title: Ibn al-Haytham

text: In mathematics, Alhazen built on the mathematical works of Euclid and Thabit ibn Qurra and worked on "the beginnings of the link between algebra and geometry".


title: Ibn al-Haytham

text: He developed a formula for summing the first 100 natural numbers, using a geometric proof to prove the formula.


title: Ibn al-Haytham

text: Alhazen explored what is now known as the Euclidean parallel postulate, the fifth postulate in Euclid's "Elements", using a proof by contradiction, and in effect introducing the concept of motion into geometry. He formulated the Lambert quadrilateral, which Boris Abramovich Rozenfeld names the "Ibn al-Haytham–Lambert quadrilateral".


title: Ibn al-Haytham

text: In elementary geometry, Alhazen attempted to solve the problem of squaring the circle using the area of lunes (crescent shapes), but later gave up on the impossible task. The two lunes formed from a right triangle by erecting a semicircle on each of the triangle's sides, inward for the hypotenuse and outward for the other two sides, are known as the lunes of Alhazen; they have the same total area as the triangle itself.


title: Ibn al-Haytham

text: Alhazen's contributions to number theory include his work on perfect numbers. In his "Analysis and Synthesis", he may have been the first to state that every even perfect number is of the form 2(2 − 1) where 2 − 1 is prime, but he was not able to prove this result; Euler later proved it in the 18th century, and it is now called the Euclid–Euler theorem.


title: Ibn al-Haytham

text: Alhazen solved problems involving congruences using what is now called Wilson's theorem. In his "Opuscula", Alhazen considers the solution of a system of congruences, and gives two general methods of solution. His first method, the canonical method, involved Wilson's theorem, while his second method involved a version of the Chinese remainder theorem.


title: Ibn al-Haytham

text: Alhazen discovered the sum formula for the fourth power, using a method that could be generally used to determine the sum for any integral power. He used this to find the volume of a paraboloid. He could find the integral formula for any polynomial without having developed a general formula.


title: Ibn al-Haytham

text: Alhazen also wrote a "Treatise on the Influence of Melodies on the Souls of Animals", although no copies have survived. It appears to have been concerned with the question of whether animals could react to music, for example whether a camel would increase or decrease its pace.


title: Ibn al-Haytham

text: In engineering, one account of his career as a civil engineer has him summoned to Egypt by the Fatimid Caliph, Al-Hakim bi-Amr Allah, to regulate the flooding of the Nile River. He carried out a detailed scientific study of the annual inundation of the Nile River, and he drew plans for building a dam, at the site of the modern-day Aswan Dam. His field work, however, later made him aware of the impracticality of this scheme, and he soon feigned madness so he could avoid punishment from the Caliph.


title: Ibn al-Haytham

text: In his "Treatise on Place", Alhazen disagreed with Aristotle's view that nature abhors a void, and he used geometry in an attempt to demonstrate that place ("al-makan") is the imagined three-dimensional void between the inner surfaces of a containing body. Abd-el-latif, a supporter of Aristotle's philosophical view of place, later criticized the work in "Fi al-Radd 'ala Ibn al-Haytham fi al-makan" ("A refutation of Ibn al-Haytham’s place") for its geometrization of place.


title: Ibn al-Haytham

text: Alhazen also discussed space perception and its epistemological implications in his "Book of Optics". In "tying the visual perception of space to prior bodily experience, Alhazen unequivocally rejected the intuitiveness of spatial perception and, therefore, the autonomy of vision. Without tangible notions of distance and size for


title: Ibn al-Haytham

text: correlation, sight can tell us next to nothing about such things." Alhazen came up with many theories that shattered what was known of reality at the time. These ideas of optics and perspective did not just tie into physical science, rather existential philosophy. This led to religious viewpoints being upheld to the point that there is an observer and their perspective, which in this case is reality.


title: Ibn al-Haytham

text: Alhazen was a Muslim and most sources report that he was a Sunni and a follower of the Ash'ari school. Ziauddin Sardar says that some of the greatest Muslim scientists, such as Ibn al-Haytham and Abū Rayhān al-Bīrūnī, who were pioneers of the scientific method, were themselves followers of the Ashʿari school of Islamic theology. Like other Ashʿarites who believed that faith or "taqlid" should apply only to Islam and not to any ancient Hellenistic authorities, Ibn al-Haytham's view that "taqlid" should apply only to prophets of Islam and not to any other authorities formed the basis for much of his scientific skepticism and criticism against Ptolemy and other ancient authorities in his "Doubts Concerning Ptolemy" and "Book of Optics".


title: Ibn al-Haytham

text: Alhazen wrote a work on Islamic theology in which he discussed prophethood and developed a system of philosophical criteria to discern its false claimants in his time.


title: Ibn al-Haytham

text: He also wrote a treatise entitled "Finding the Direction of Qibla by Calculation" in which he discussed finding the Qibla, where prayers (salat) are directed towards, mathematically.


title: Ibn al-Haytham

text: Alhazen made significant contributions to optics, number theory, geometry, astronomy and natural philosophy. Alhazen's work on optics is credited with contributing a new emphasis on experiment.