Parmenides was a Greek philosopher from Elea who founded the School of Elea. He believed that all changes are an illusion and that there is only one reality which is finite, uniform, motionless, and can only be understood through reason rather than sensory experience. Parmenides' disciple Zeno used logical arguments to support Parmenides' view that motion is an illusion. Pythagoras also founded a philosophical school with many followers. He made important contributions to mathematics, astronomy, and music theory. Pythagoras believed that numbers are fundamental to understanding the universe and applied mathematical principles to many aspects of human existence. He observed the harmonic relationships in string lengths that produce pleasant tones, which may have been