Islamic views on evolution are diverse, ranging from theistic evolution to Old Earth creationism. Some Muslims around the world believe "humans and other living things have evolved over time", yet some others believe they have "always existed in present form". Some Muslims believe that the processes of life on Earth started from one single point of species with a mixture of water and a viscous clay-like substance. Muslim thinkers have proposed and accepted elements of the theory of evolution, some holding the belief of the supremacy of God in the process. Some scholars suggested that both narratives of creation and of evolution, as understood by modern science, may be believed by modern Muslims as addressing two different kinds of truth, the revealed and the empirical. Others argue that faith and science can be integrated and complement each other. History Early views In ('Book of the Animals'), the 9th-century Muslim scholar al-Jāḥiẓ references several facets of natural selection, such as animal embryology, adaptation, and animal psychology. One notable observation al-Jāḥiẓ makes is that stronger rats were able to compete better for resources than small birds, a reference to the modern day theory of the "struggle for existence". Al-Jāḥiẓ also wrote descriptions of food chains. In 10th century Basra, an Islamic Encyclopedia titled Encyclopedia of the Brethren of Purity introduced the earliest attested evolutionary framework. The Encyclopedia expanded on the Platonic and Aristotelian concept of the great chain of being by proposing a causal relationship advancing up the chain as the mechanism of creation, beginning with the creation of matter and its investment with energy, thereby forming water vapour, which in turn became minerals and "mineral life". Coral, with its branch-like structure, was the highest mineral life which gave rise to lower plants. The date palm was considered the highest plant, giving rise to lower animals, and then through apes came barbarian man, followed by superior man, including the saints and the prophets. Thereafter the chain continues in the traditional form using less causal clarity, with the angels being above man, and above the angels being God as both the originator and the pinnacle. Muhammad Hamidullah summarises this concept found in the work: "Everything begins from Him and everything returns to Him." However, some scholars also criticized and dismissed the Brethren text reading as a proof on pre-Darwinian evolution theory. According to Sami S. Hawi, the 11th-century Persian scholar Ibn Miskawayh wrote