H. G. A. to H. M.

I suppose that Hartley has been greatly over-estimated, and that his philosophy was founded chiefly on a rather superficial generalization of Newton's theory of vibrating media. I do not wonder at your disrelish of the metaphysicians who have had no basis of agreement. Mind was divided and parcelled out into divisions or categories, by each writer as his fancy suggested, every one differing from the others, and each thinking himself most profound, and as certain of his position as any sectarian is of the evidence and principles of his particular faith. You would find several distinct faculties included under one term; and then a simple faculty split into several; or a mode of action taken for a primitive faculty. Thus Mind was divided into imaginary elements, just as Nature has been divided. Or you would find men building all the laws of Mind on some one fact, such as the principle of Association,—just as the laws of Nature were supposed to be included in the laws of Numbers. Thus Mind was fashioned into fanciful forms by the metaphysicians, while the physiologists were, on the other hand, slicing up the brain as they would a turnip, instead of unfolding it, part from part, and nerve by nerve, so as to trace out its intimate union, relations, and true formation, and place in the scale of beings.