[Kepler] had to realize clearly that logical-mathematical theoretizing, no matter how lucid, could not guarantee truth by itself; that the most beautiful logical theory means nothing in natural science without comparison with the exactest experience. Without this philosophic attitude, his work would not have been possible.
Albert EinsteinThe man who regards his own life and that of his fellow-creatures as meaningless is not merely unfortunate but almost disqualified for life.
Albert EinsteinTime has no independent existence apart from the order of events by which we measure it.
Albert Einstein