As an adolescent I aspired to lasting fame, I craved factual certainty, and I thirsted for a meaningful vision of human life - so I became a scientist. This is like becoming an archbishop so you can meet girls.
Never tell evil of a man, if you do not know it for certainty, and if you know it for a certainty, then ask yourself, 'Why should I tell it?'
It is now proved beyond doubt that smoking is one of the leading causes of statistics.
As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality.
If we can recognize that change and uncertainty are basic principles, we can greet the future and the transformation we are undergoing with the understanding that we do not know enough to be pessimistic.
Do not expect to arrive at certainty in every subject which you pursue. There are a hundred things wherein we mortals ... must be content with probability, where our best light and reasoning will reach no farther.
Far from offering a shortcut to clairvoyance, history teaches us that the future is full of surprises and outwits all our certitudes.
I've grown certain that the root of all fear is that we've been forced to deny who we are.
It is not bigotry to be certain we are right; but it is bigotry to be unable to imagine how we might possibly have gone wrong.
But in this world nothing can be said to be certain, except death and taxes.
Your manuscript is both good and original, but the part that is good is not original and the part that is original is not good. (attributed)
The length of a film should be directly related to the endurance of the human bladder.