To ask, therefore, whether we “know” the postulates of scientific inference, is not so definite a question as it seems. The answer must be: in one sense, yes, in another sense, no; but in the sense in which “no” is the right answer we know nothing whatever, and “knowledge” in this sense is a delusive vision. The perplexities of philosophers are due, in a large measure, to their unwillingness to awaken from this blissful dream.
Source: Human Knowledge, its scope and limits, 1948, introduction.
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