J.L. Austin, answered from the texts and cited to the page.
Saying "I know" is not a stronger version of saying "I am sure" — it is a different kind of utterance altogether, on the same logical footing as "I promise." When I say "I promise," I do not describe my mental state; I commit myself, give the hearer authority, and assume responsibility should the promise fail. "I know" works the same way: I give my word, I commit, I take on the obligation of having ruled out the relevant alternatives.123
The dream argument tries to make me rule out being asleep before I can be credited with knowing what I claim to know — but unless there is a special reason to suspect I am dreaming, the demand has no purchase, just as the demand that the witness rule out narcoleptic dreaming has no purchase unless there is some specific reason to suspect she is narcoleptic.45
It is naturally always possible ('humanly' possible) that I may be mistaken or may break my word, but that by itself is no bar against using the expressions 'IT know' and 'I promise' as we do in fact use them.Philosophical Papers, p. 105
Just as promising is not something superior, in the same scale as hoping and intending, even to merely fully intending: for there is nothing in that scale superior to fully intending. When I say 'I know', I give others my word: I give others my authority for saying that 'S is P'.Philosophical Papers, pp. 106–107
But the essential factors OTHER MINDS 103 are (a) You said you knew: you said you promised (b) You were mistaken: you didn't perform. The hesitancy concerns only the precise way in which we are to round on the original 'I know' or 'I promise'. To suppose that 'I know' is a descriptive phrase, is only one example of the descriptive fallacy, so common in philosophy.Philosophical Papers, p. 109
Over these points in the two cascs parallel series of doubts are apt to infect philosophers, on the ground that I cannot foresee the future. Some begin to hold that I should never, or practically never, say I know anything—perhaps only what I am sensing at this moment: others, that I should never, or practically never, say I promise—perhaps only what is actually within OTHER MINDS IO1 my power at this moment.Philosophical Papers, p. 107
If I know I can't be wrong One final point about 'How do you know?', the challenge to the user of the expression 'I know', requires still to be brought out by consideration of the saying that 'If you know you can't be wrong'.Philosophical Papers, p. 104
The most heavily contested epistemological position in the post-war analytic literature on Austin. The standard consensus from 1964 forward (Chisholm, Cavell, Stroud, McGinn, Williams) has been that Austin granted everything about ordinary epistemic practice the skeptic could grant, and missed the philosophical context — a context with stricter standards than ordinary practice — where the skeptical question is asked. Mark Kaplan's Austin's Way with Skepticism (2018) reconstructs Austin's actual brief: the no-special-reason condition is not merely a fact about ordinary appropriate assertion but a condition on epistemological theory itself; the principle of total evidence requires that any theory of knowledge accord with everything we ordinarily and correctly say about knowing.