To find out what one is fitted to do, 

and to secure an opportunity to do it, 

is the key to happiness.

Anyone who has begun to think, 

places some portion of the world in jeopardy.

The self is not something ready-made, 

but something in continuous formation 

through choice of action.

Scientific principles and laws do not lie on the surface of nature. 

They are hidden, 

and must be wrested from nature 

by an active and elaborate technique of inquiry.

Every great advance in science 

has issued from a new audacity 

of imagination.