That question is not, save upon the assumption of the ubiquity of the knowledge relation, the absurd question of whether knowledge makes any difference to things already known or to things as knowledge-objects, as facts or truths.
Until the epistemological realists have seriously considered the main propositions of the pragmatic realists, viz., that knowing is something that happens to things in the natural course of their career, not the sudden introduction of a "unique" non-natural type of relation-that to a mind or consciousness-they are hardly in a position to discuss the second and derived pragmatic proposition that, in this natural continuity, things in becoming known undergo a specific and detectable qualitative change.
I had occasion earlier to remark that if one identifies "knowledge" with situations involving the function of inference, the problem of knowledge means the art of guiding this function most effectively. That statement holds when we take knowledge as a relation of the things in the knowledge situation. If we are once convinced of the artificiality of the notion that the knowledge relation is ubiquitous, there will be an existential problem as to the self and knowledge; but it will be a radically different problem from that discussed in epistemology. The relation of knowing to existence will be recognized to form the subject-matter of no problem, because involving an ungrounded and even absurd preconception. But the problem of the relation of an existence in the way of knowing to other existences-or events-with which it forms a continuous process will then be seen to be a natural problem to be attacked by natural methods.
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