This is a fairly sophisticated view of how light actually works. And he's also credited with using and understanding the scientific method several hundred years before the Renaissance in Europe. The duty of a man, the duty of the man who investigates the writing of scientists, if learning the truth is his goal, is to make himself an enemy of all that he reads and attack it from every side. He should also suspect himself as he performs his critical examination of it so that he may avoid falling into either prejudice or leniency. And now another very famous poet, philosopher, mathematician, polymath of the time was Omar Khayyam. And in the West, he is most famous for his poetry, most famously the work of the Rubaiyat, the translation by Fitzgerald. But he was also a significant philosopher, mathematician.