True originality consists not in a new manner but in a new vision.

The atavistic urge toward danger persists and its satisfaction is called adventure.

I learned to make my mind large, as the universe is large, so that there is room for paradoxes.

How gloriously legible are the constellations of the heavens!

Appearances are a glimpse of the obscure.

Every man takes the limits of his own field of vision for the limits of the world.

Research is formalized curiosity. It is poking and prying with a purpose. 

When they shout “Long live progress,” always ask, “Progress of what?”

The eternal mystery of the world is its comprehensibility.

Nature has planted in our minds an insatiable desire to seek the truth.