Lope K. Santos (born Lope Santos y Canseco, September 25, 1879 – May 1, 1963) was a Filipino Tagalog-language writer and former senator of the Philippines. He is best known for his 1906 socialist novel, Banaag at Sikat and to his contributions for the development of Filipino grammar and Tagalog orthography. Lope K. Santos was born in Pasig, Province of Manila (now a part of Metro Manila) as Lope Santos y Canseco to Ladislao Santos, a native of Pasig, and Victorina Canseco, a native of San Mateo, on September 25, 1879. He was raised in Pandacan. His father was imprisoned during Philippine Revolution because Spanish authorities found copies of José Rizal's Noli Me Tangere and Ang Kalayaan in his possession. Santos was sent to Escuela Normal Superior de Maestros (Higher Normal School for Teachers) for education and later finished schooling at Colegio Filipino. During Philippine Revolution of 1896, Santos joined revolutionaries. By the time of the death of his mother, she requested Lope to marry Simeona Salazar. Marriage happened on February 10, 1900 and they were blessed with three children namely Lakambini, Luwalhati and Makaaraw. He pursued law at the Academia de la Jurisprudencia then at Escuela de Derecho de Manila (now Manila Law College Foundation) where he received Bachelor of Arts degree in 1912. In late 1900, Santos started writing his own newspaper Ang Kaliwanagan. This was also the time when socialism becomes an emerging idea in world ideology. When José Ma. Dominador Goméz was charged and sentenced by the Supreme Court of sedition and illegal association against the government in 1903, Goméz's labor group Union Obrera Democratica Filipina (Philippine Democratic Labor Union) was absorbed by Santos. The group was renamed as Union del Trabajo de Filipinas, but was later dissolved in 1907. In 1903, Santos started publishing fragments of his first novel, Banaag at Sikat (From Early Dawn to Full Light) on his weekly labor magazine Muling Pagsilang (The Rebirth) and was completed in 1906. When published in book form, Santos' Banaag at Sikat was then considered the first socialist-oriented book in the Philippines that expounded principles of socialism and sought labor reforms from the government. The book later became an inspiration for the assembly of the 1932 Socialist Party of the Philippines and then the 1946 group Hukbalahap. Santos became expert in dupluhan, a form of poetical debate during that time. Dupluhan can be compared to balagtasan,