Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute. That's relativity.
The hardest thing in the world to understand is income tax.
When his wife asked him to change clothes to meet the German Ambassador, he said, "If they want to see me, here I am. If they want to see my clothes, open my closet and show them my suits."
With fame I become more and more stupid, which of course is a very common phenomenon.
You do not really understand something unless you can explain it to your grandmother.
The difference between genius and stupidity is that genius has its limits.
Make everything as simple as possible, but not simpler.
If I had only known, I would have been a locksmith.
Reality is merely an illusion, albeit a very persistent one.
Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy
Education is what remains after one has forgotten everything he learned in school.
Common sense is the collection of prejudices acquired by age 18.
If A is a success in life, then A equals x plus y plus z. Work is x; y is play; and z is keeping your mouth shut.
Men marry women with the hope they will never change. Women marry men with the hope they will change. Invariably they are both disappointed.
We can't solve problems by using the same kind of thinking we used when we created them.
The secret of creativity is knowing how to hide your sources.
Any intelligent fool can make things bigger and more complex. It takes a touch of genius and a lot of courage to move in the opposite direction.
Life is like riding a bicycle. To keep your balance you must keep moving.
Intellectuals solve problems; geniuses prevent them.
Imagination is more important than knowledge.
Not everything that counts can be counted, and not everything that can be counted counts.
I never think of the future. It comes soon enough.
Insanity: doing the same thing over and over again and expecting different results.
It is a miracle that curiosity survives formal education.
It's not that I'm so smart, it's just that I stay with problems longer.