The world is not full of evil because of those who do wrong. It is full of evil because of those who do nothing.

If God has created the world, his primary worry was certainly not to make its understanding easy for us

Nature hides her secrets because of her essential loftiness, but not by means of ruse.

The harmony of natural law reveals an Intelligence of such superiority that, compared with it, all the systematic thinking and acting of human beings is an utterly insignificant reflection.

If one tries to navigate unknown waters one runs the risk of shipwreck

Gradually the conviction gained recognition that all knowledge about things is exclusively a working-over of the raw material furnished by the senses. ... Galileo and Hume first upheld this principle with full clarity and decisiveness.

Understanding physics is child's play when compared to understanding child's play.