Great Philosopher: ابن سینا, ibn Sina, Avicenna

ابن سینا, ibn Sina and known in the West as Avicenna, was one of the greatest ancient philosophers. His work covered many areas of knowledge. Notably his book The Cannon of Medicine was the standard medical textbook through the 18th century in Europe as well as his religious thinking such as the Floating Man Argument and his proof of Gods existence.