Peirce is the most original philosopher America produced and he could not hold a job. He was dismissed from Johns Hopkins in 1884 after five years, never taught again, lost his Coast Survey income in 1891, and spent his last two decades at a farm in Pennsylvania writing manuscripts nobody published, kept going partly by money from William James.

He left around eighty thousand sheets. Almost everything he is now read for came out after 1931.

The maxim, in the form he meant it

The founding statement of pragmatism is one sentence from an 1878 paper, How to Make Our Ideas Clear:

> Consider what effects, which might conceivably have practical bearings, we > conceive the object of our conception to have. Then, our conception of these > effects is the whole of our conception of the object.

Read it carefully, because the careless reading is what the rest of his life was spent objecting to.

It is a rule for clarifying a concept, not a test of truth and not a theory of meaning-as-usefulness. Take a term, work out what difference it would make if it applied, and that difference is the content of the term. Two concepts with identical conceivable consequences are the same concept differently worded. A concept with no conceivable consequences has no content to argue about.

Note the word conceivably. It does not ask what use a belief is to you. It asks what would be the case if the thing were so — which is a question about the world, and which is precisely the restriction that got dropped when the doctrine became popular.

Abduction

His most useful contribution to how inquiry actually works, and the one that had no name before him.

Deduction draws out what is already in the premises and adds nothing. Induction generalizes from observed cases and tells you how far a pattern extends. Neither of them produces a new idea. Something has to supply the hypothesis that the other two then work on, and that step — the leap to a candidate explanation — Peirce called abduction.

His point is that it is a form of inference rather than a mystery or a flash of genius. It has a structure: a surprising fact is observed; if a certain hypothesis were true, the fact would follow as a matter of course; so there is reason to suspect the hypothesis. It is the weakest of the three and the only one that moves.

The contemporary literature on inference to the best explanation is his analysis under a later name, and it is the step that tidy accounts of the scientific method leave out.

Fallibilism, and who does the verifying

Two doctrines that only work together.

Nothing is immune to revision. Not the best-established belief, not the mathematics, not the thing everyone is sure of. This is not skepticism — he thought inquiry succeeded — but a claim about the status of any result at any moment, and it is the ancestor of falsifiability without Popper's sharp line.

And verification is not something an individual does. It belongs to a community of inquirers extended over indefinite time, which gives his definition of truth: what that community would converge on at the limit of inquiry. A finite person works with the best that inquiry has so far supported, and calls it true provisionally, and means something specific by the provisionality.

This is the part that makes his pragmatism harder than the popular version. Truth is what inquiry would end at, not what it is convenient to believe now, and no living person gets to check.

The quarrel with James

James's 1898 lecture brought pragmatism to public attention and changed it on the way. Where Peirce had a rule for clarifying concepts, James produced a theory of truth in which a belief is true if it works — if believing it pays in experience.

Peirce spent years objecting, and in 1905 renamed his own position pragmaticism, a word he described as ugly enough to be safe from kidnappers. The objection was not territorial. On his account the maxim asks what would follow in the world; James's version asks what follows for the believer, and that substitution makes truth a property of how a belief sits with a person. Cheryl Misak's recovery of Peirce over the last two decades has argued that the stricter version is the defensible one, and that a century of dismissing pragmatism as relativism was dismissing James's formulation rather than the position.

The objection

The system is partly a reconstruction, and the reconstruction is not his.

He published a fraction of his work, left the rest unsorted across eighty thousand sheets, and the Collected Papers of 1931–58 arranged that material topically — cutting across decades, splicing passages from different periods, and presenting as a settled architecture something he was still arguing with himself about. The chronological Indiana edition, still unfinished after forty years, exists because scholars concluded the first one had made a system out of a life's notes.

So claims about what Peirce held have to specify when, and a good deal of what is confidently attributed to him is an editor's arrangement. The logic and the semiotics survive this best, because they were worked out and in some cases published. The late metaphysics — the objective idealism, the cosmology — survives it least.