The Commens Dictionary
Quote from ‘Pragmatism’
…in this original exposition, I laid down, in the very first place, the doctrine of Common Sense; namely, that there are some propositions that a man, as a fact, does not doubt; and what he does not doubt, he can, at most, make but a futile pretense to criticize. The test of doubt and belief is conduct. No sane man doubts that fire would burn his fingers; for if he did he would put his hand in the flame, in order to satisfy his doubt. There are some beliefs, almost all of which relate to the ordinary conduct of life, such as that ordinary fire burns the flesh, [which] while pretty vague, are beyond the reach of any man’s doubt. When the analysis of the meaning of a concept has carried us to such a “practical” matter, it is idle to go further in analyzing it into a habit of conduct. But along with such “instinctive” beliefs, as we may call them, because, however they came about, they resemble the instincts of the lower animals, there are a good many formulae, almost universally accepted, which mean nothing, or, at any rate, nothing indubitable. For example, one often hears it said, “I could no more doubt that than I doubt of my own existence.” But, after all, what does a man mean when he says that he exists? By what concrete experiments in the imagination will he exemplify his meaning? I will not stop to discuss this particular proposition. I will only say that if we are to admit that some propositions are beyond our powers of doubt, we must not admit any specified proposition to be of this nature without severe criticism; nor must any man assume with no better reason than because he cannot doubt it, that another man cannot do so. These remarks give some idea of what is meant by critical common sense, without which the doctrine of pragmatism amounts to very little.
Here, "this original exposition" refers to 'The Fixation of Belief' (1877) and 'How to Make Our Ideas Clear' (1878)