"We have not known a single great scientist who could not discourse freely and interestingly with a child. Can it be that haters of clarity have nothing to say, have observed nothing, have no clear picture of even their own fields?"

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The history of science, like the history of all human ideas, is a history of irresponsible dreams, of obstinacy, and of error. But science is one of the very few human activities-perhaps the only one-in which errors are systematically criticized and fairly often, in time, corrected. This is why we can say that, in science, we often learn from our mistakes, and why we can speak clearly and sensibly about making progress there. In most other fields of human endeavour there is change, but rarely progress ... And in most fields we do not even know how to evaluate change.

— Karl Popper