Reality is merely an illusion, albeit a very persistent one.
For every one billion particles of antimatter, there were one billion and one particles of matter. And when the mutual annihilation was complete, one billionth remained -- and that's our present universe.
As a human being, one has been endowed with just enough intelligence to be able to see clearly how utterly inadequate that intelligence is when confronted with what exists.
The measure of success is not whether you have a tough problem to deal with, but whether or not it is the same problem you had last year.
The most useful thing about a principle is that it can always be sacrificed to expediency.
It is the characteristic of the most stringent censorships that they give credibility to the opinions they attack.
It will be found an unjust and unwise jealousy to deprive a man of his natural liberty upon the supposition he may abuse it.
Advertising may be described as the science of arresting the human intelligence long enough to get money from it.
Only those who risk going too far can possibly find out how far one can go.
On the subject of wild mushrooms, it is easy to tell who is an expert and who is not: The expert is the one who is still alive.