In short, we may admit with D’Alembert, quoted in the Dissertations, “That the truth in metaphysics, like the truth in matters of taste, is a truth of which all minds have the germ within themselves; to which, indeed, the greater number pay no attention, but which they recognise the moment it is pointed out to them. . . But if, in this sort, all are able to understand, all are not able to instruct. The merit of conveying easily to others true and simple notions is much greater than is commonly supposed; for experience proves how rarely this is to be met with. Sound metaphysical ideas are the common truths which every one apprehends, but which few have the talent to develop.” “The first problem of philosophy,” adds the Scottish philosopher, “and it is one of no easy accomplishment, being thus to seek out, purify, and establish, by intellectual analysis and criticism, the elementary feelings and beliefs, in which are given the elementary truths of which all are in possession; and the argument from common sense being the allegation of those feelings and beliefs, as explicated and ascertained, in proof of the relative truths and their necessary consequences, this argument is manifestly dependent on philosophy as an art, as an acquired dexterity, and cannot, notwithstanding the errors which they have frequently committed, be taken out of the hands of philosophers. Common sense is like common law. Each may be laid down as the general rule of decision; but in one case it must be left to the jurist, in the other to the philosopher, to ascertain what are the contents of the rule; and though in both cases the common
