It was necessary to be thus particular about Hartley’s doctrine on the generation of ideas, because, as expressed in the above passages, it is one of the broadest statements of Externalism possible, and if consistently followed out, as it has been by the Mills, neither morals nor mathematics can escape from its grasp. According to this doctrine there exists no morality founded on the eternal reasons and relations of things, but all notions of right and wrong proceed from association alone, from clusters of ideas which are only modified sensations,--all affection as well as all reasoning being the mere result of association--(i. 499.) Let us now inquire a little more closely what this ASSOCIATION is, which performs such marvels in the transmutation of sensations into ideas; for surely never was a word so largely used by philosophical writers in recent times, and so villainously abused. Association is a popular term, and therein precisely lies its large capacity of doing harm, when sophistically used. Now what it means in popular language is pretty plain. When I think of London I think of beauty, splendour, magnitude, multitude, wealth, din, incalculable noise of rattling cabs above ground and of screeching railways under ground. These are my associations with London. When I think of Oxford, I think of Greek and Grammars and square caps, of {291} mitres, and lawn sleeves, High Church and Broad Church, learning and luxury, bigotry and boating, cricket, cram, and scholarly conceit. When I think of the Highlands, I think of Bens and Glens, of lochs and waterfalls, of steamboats and tourists, of salmon-fishing, grouse-shooting, deerstalking. Free Churches, untrousered legs, and Ossianic poems. There does not seem much mystery in this. Ideas must hang together somehow or other; if they did not, they would be like a swarm of mad bees in our head, and would reel about in an unmanageable chaos; if therefore they are to hang together in some way, what more natural than that those ideas which come in together should remain together, and that those which have a family likeness and affinity should arrange themselves into companies. Add to this the natural tendency of black to recall white, and of life to suggest death, and you have the whole three bonds of association among human thoughts and emotions--contiguity, similarity, and contrast--of which philosophical writers make parade. Now what is the place which belongs to this popular principle of association in a system of metaphysics or mental philosophy? To me its place appears a very secondary one; and to give it any place at all we must carefully distinguish between accidental and necessary, between ephemeral and eternal associations, the confounding of which rather seems to stand out as the prominent employment of the Sensation philosophers. There are two great classes of associations, the one principally of external and accidental, the other of internal and necessary origin; the one