Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1885 edition. Excerpt: ... CONCLUSION. THE IMMEDIATE PREMISE. I WILL end with a word on the foundations of knowledge arising out of the instance of the vernier. Too much, to my mind, has been said of late years about the immediate necessity of the ultimate judgments on which knowledge rests, and about the final dependence of science on the trained perception of the individual. I have expressed my dissent from this doctrine near the beginning of these remarks, and wish to insist upon it at their close. Trained perception is of course essential to science. And, though loaded with inference, yet such perception becomes so rapid and so sure, that to insist upon its inferential character seems pedantic. But there is much exaggeration and confusion upon this subject. The trained eye is more accurate than the untrained eye; but not to a degree which so much as tends to account for the value of scientific observation as compared with ordinary looking. In very precise measurement, e.g. with a micrometer, the coincidence of two visible marks is the ultimate fact of perception. No doubt the trained observer will establish a coincidence more exactly, or will estimate a small discrepancy far more precisely, than most untrained observers can. But this advantage is not the measure, is not in most cases an appreciable part of the measure, of the greater precision of his observation compared with that of the layman, if the layman were left to describe his own observation. If, on the contrary, the layman merely looks where he is told, and notes the coincidence of marks which a man of science tells him to note, and the observation is recorded and interpreted by the latter, then it is (barring a sheer blunder on the layman's part, to which, as I have shown, he is very liable if left...