Look deep into nature, and then you will understand everything better.

Mere thinking cannot reveal to us the highest purpose.

For an idea which, at first, does not seem absurd, there is no hope.

The world as we see it is only the world as we see it. Others may see it differently.

To the Master's honor all must turn, each in its track, without a sound, forever tracing Newton's ground.

The great need to grasp principles had caused me to spend most of my time on fruitless persuits.

An oligarchy of private capital cannot be effectively checked even by a democratically organized political society because under existing conditions, private capitalists inevitably control, directly or indirectly, the main sources of information.