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Absolute knowledge (at least, as a result of discourse) is impossible.
No discourse whatsoever can end in absolute knowledge of fact, past or to come. For, as for the knowledge of fact, it is originally sense, and ever after memory. And for the knowledge of consequence, which I have said before is called science, it is not absolute, but conditional. No man can know by discourse that this, or that, is, has been, or will be; which is to know absolutely: but only that if this be, that is; if this has been, that has been; if this shall be, that shall be; which is to know conditionally: and that not the consequence of one thing to another, but of one name of a thing to another name of the same thing.
Hobbes, Lev VII 3