From the "Our sense of sight in disclosing to us the sweep of the heavens and the patterns of change in its several parts, is the most important stimulus to the perennial human search for understanding in the universe in which we live. 'The sight' Plato has Timaeus say at one point in his memorable discourse, 'in my opinion is the source of the greatest benefit to us, for had we never seen the stars, and the sun, and the heaven, none of the words which we have spoken about the universe would ever have been uttered....'"