Essays on the Active Powers of the Human Mind

Abstract

This very ingenious author adopts the principle of Mr Locke before mentioned—that all our simple ideas are derived either from sensation or reflection. This he seems to understand, even in a stricter sense than Mr Locke did. For he will have all our simple ideas to be copies of preceding impressions, either of our external senses or of consciousness. “After the most accurate examination,” says he, “of which I am capable, I venture to affirm, that the rule here holds without any exception, and that every simple idea has a simple impression which resembles it, and every simple impression a correspondent idea. Every one may satisfy himself in this point, by running over as many as be pleases.”* I observe here, by the way, that this conclusion is formed by the author rashly and unphilosophically. For it is a conclusion that admits of no proof, but by induction; and it is upon this ground that he himself founds it. The induction cannot be perfect till every simple idea that can enter into the human mind be examined, and be shewn to be copied from a resembling impression of sense or of consciousness. No man can pretend to have made this examination of all our simple ideas without exception; and, therefore, no man can, consistently with the rules of philosophizing, assure us, that this conclusion holds without any exception.[27] The author professes, in his title page, to introduce into moral subjects the experimental method of reasoning. This was a very laudable attempt; but he ought to have known, that it is a rule in the experimental method of reasoning, that conclusions, established by induction ought never to exclude exceptions, if any such should afterward appear from observation or experiment. Sir Isaac Newton, speaking of such conclusions, says, “Et si quando in experiundo postea, reperiatur aliquid, quod a parte contraria faciat; tum demum, non sine istis exceptionibus affirmetur conclusio opportebit.”** “But,” says our author, “I will venture to affirm, that the rule here holds without any exception.”