The difference between stupidity and genius is that genius has its limits.

The devil has put a penalty on all things we enjoy in life. Either we suffer in health or we suffer in soul or we get fat.

Love is a better teacher than duty.

Only two things are infinite, the universe and human stupidity, and I’m not sure about the former.

Our task must be to free ourselves by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty.

The only thing that interferes with my learning is my education.

It is my conviction that killing under the cloak of war is nothing but an act of murder.

As far as I’m concerned, I prefer silent vice to ostentatious virtue.

Concern for man and his fate must always form the chief interest of all technical endeavors. Never forget this in the midst of your diagrams and equations.

Finally Germany’s attack on Russia seemed to confirm that Russia was not shirking and was prepared to carry out a foreign policy with the risk of war with Germany.

There comes a time when the mind takes a higher plane of knowledge but can never prove how it got there.

There are two ways to live: you can live as if nothing is a miracle; you can live as if everything is a miracle.

He who joyfully marches in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would suffice.

I do not believe in immortality of the individual, and I consider ethics to be an exclusively human concern with no superhuman authority behind it.

The Communist Party said that I must finish my studies because after the revolution in Germany people would be required with technical knowledge to take part in the building of the Communist Germany.

Nothing is more destructive of respect for the government and the law of the land than passing laws which cannot be enforced.

Intellectuals solve problems, geniuses prevent them.

All that is valuable in human society depends upon the opportunity for development accorded the individual.

There could be no fairer destiny for any physical theory than that it should point the way to a more comprehensive theory in which it lives on as a limiting case.

It’s not that I’m so smart, it’s just that I stay with problems longer.

Occurrences in this domain are beyond the reach of exact prediction because of the variety of factors in operation, not because of any lack of order in nature.

God always takes the simplest way.

Politics is for the present, but an equation is for eternity.

I carried on the negotiations with the leaders of the Nazi group at the University, proposing that we should organize a strike of the students.

It was the experience of mystery – even if mixed with fear – that engendered religion.

Pure mathematics is, in its way, the poetry of logical ideas.

Most people say that is it is the intellect which makes a great scientist. They are wrong: it is character.

We should take care not to make the intellect our god; it has, of course, powerful muscles, but no personality.

The last time when I handed over information was in February or March 1949.

The value of a man should be seen in what he gives and not in what he is able to receive.

Few are those who see with their own eyes and feel with their own hearts.

Insanity: doing the same thing over and over again and expecting different results.

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

You ask me if I keep a notebook to record my great ideas. I’ve only ever had one.

Let every man be respected as an individual and no man idolized.

Human beings must have action; and they will make it if they cannot find it.

The gift of fantasy has meant more to me than my talent for absorbing positive knowledge.

I had therefore, no hesitation in giving all the information I had, even though occasionally I tried to concentrate mainly on giving information about the results of my own work.

The road to perdition has ever been accompanied by lip service to an ideal.

Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted.

Before God we are all equally wise – and equally foolish.

Make everything as simple as possible, but not simpler.

There is nobody I know by name who is concerned with collecting information for the Russian authorities. There are people whom I know by sight whom I trusted with my life.

Solitude is painful when one is young, but delightful when one is more mature.

The fear of death is the most unjustified of all fears, for there’s no risk of accident for someone who’s dead.

Things should be made as simple as possible, but not any simpler.

In the post war period I began again to have my doubts about Russian policy.

Not everything that can be counted counts, and not everything that counts can be counted.

He who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed.

I believe that a simple and unassuming manner of life is best for everyone, best both for the body and the mind.