Digital Companion to C. S. Peirce

Some Wit, Wisdom & Bewilderment

...knowledge is nothing, quite nothing but a counterfeit, unless it would under some circumstances determine conduct. It must have real effects. In fact any outward sign must, not merely as a thing, but as a sign produce physical effects in order to be communicated. And any inward sign must doubtless produce physical effects, as a sign.
Dichotomic Mathematics, 1904