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.

Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.

We must dedicate our lives to drying up the source of war: ammunition factories.

In quitting this strange world he has once again preceded me by a little. That doesn't mean anything. For those of us who believe in physics, this separation between past, present, and future is only an illusion, however tenacious.

The history of scientific and technical discovery teaches us that the human race is poor in independent and creative imagination. Even when the external and scientific requirements for the birth of an idea have long been there, it generally needs an external stimulus to make it actually happen; man has, so to speak, to stumble right up against the thing before the idea comes.

One must not attempt to justify them, but rather to sense their nature simply and clearly.

Not all that counts, can be counted