Richard P. Feynman Doubt Quotations

We absolutely must leave room for doubt or there is no progress and no learning. There is no learning without having to pose a question. And a question requires doubt. People search for certainty. But there is no certainty.

Religion is a culture of faith; science is a culture of doubt.

We need to teach how doubt is not to be feared but welcomed. It's OK to say, "I don't know."

There is no harm in doubt and skepticism, for it is through these that new discoveries are made.

Science is a way to teach how something gets to be known, what is not known, to what extent things are known (for nothing is known absolutely), how to handle doubt and uncertainty, what the rules of evidence are, how to think about things so that judgments can be made, how to distinguish truth from fraud, and from show.

There is no learning without having to pose a question. And a question requires doubt.

Doubt is clearly a value in science. It is important to doubt and that the doubt is not a fearful thing, but a thing of great value.

When a scientist doesn't know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty darn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of uncertainty-some most unsure, some nearly sure, but none absolutely certain.

A scientist is never certain. ... We absolutely must leave room for doubt or there is no progress and there is no learning.

We have found it of paramount importance that in order to progress, we must recognize our ignorance and leave room for doubt.

Another of the qualities of science is that it teaches the value of rational thought, as well as the importance of freedom of thought; the positive results that come from doubting that all the lessons are true... Learn from science that you must doubt the experts. As a matter of fact, I can also define science another way: Science is the belief in the ignorance of experts.

You see, one thing is, I can live with doubt and uncertainty and not knowing. I have approximate answers and possible beliefs and different degrees of certainty about different things... It doesn't frighten me.