I'd rather be an optimist and a fool than a pessimist and right.
How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality?
The most important decision we make is whether we believe we live in a friendly or hostile universe.
Logic will get you from A to B. Imagination will take you everywhere.
The number of natural hypothesis that can explain any given phenomena is infinite.
Whoever is devoid of the capacity to wonder, whoever remains unmoved, whoever cannot contemplate or know the deep shudder of the soul in enchantment, might just as well be dead for he has already closed his eyes upon life.