499-428 B.C.

Greek philosopher who made the first known efforts toward squaring the circle, and who provided an early scientific cosmology. According to the Roman architect Vitruvius (first century A.D.), Anaxagoras also wrote a treatise on how to paint objects such that those in the background appeared smaller than those in the foreground—in other words, how to use perspective. Anaxagoras anticipated the scientists of the Enlightenment by some 2,000 years with an account of the Solar System as a material, rather than an ethical, entity; and was the first thinker known to have stated that the Moon's light is a reflection of the Sun's.