Richard Feynman on Ignorance in Science

It is impossible for a man to learn what he thinks he already knows—Epictetus

Without recognizing our ignorance, we cannot make progress. As Richard Feynman writes in What Do You Care What Other People Think (emphasis mine):

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 certainty—some most unsure, some nearly sure, but none absolutely certain.

This does not come naturally to us, especially when signalling perfect confidence seems to be a virtue. As with any other skill, we should practice overcoming our ego and admitting our ignorance. This is what scientists need to do to advance a field:

The scientist has a lot of experience with ignorance and doubt and uncertainty, and this experience is of very great importance, I think. 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.

However, this is not a monopoly of science; we can (and should) embrace doubt.

It is our responsibility as scientists, knowing the great progress which comes from a satisfactory philosophy of ignorance, the great progress which is the fruit of freedom of thought, to proclaim the value of this freedom; to teach how doubt is not to be feared but welcomed and discussed; and to demand this freedom as our duty to all coming generations.