It may happen, indeed, in both cases, that A may raise a particular miniature, as b, preferably to any of the rest, from its being more associated with B, from the novelty of the impression of B, from a tendency in the medullary substance to favour b, &c. and in like manner, that b may raise c or d preferably to the rest. However, all this will be over-ruled, at last, by the recurrency of the associations; so that any one of the sensations will excite the ideas of the rest at the same instant, i.e. associate them together.
Case 3. Let A, B, C, D, &c. represent successive impressions, it follows from the tenth and eleventh propositions, that A will raise b, c, d, &c. B raise c, d, &c. And though the ideas do not, in this case, rise precisely at the same instant, yet they come nearer together than the sensations themselves did in their original impression; so that these ideas are associated almost synchronically at last, and successively from the first. The ideas come nearer to one another than the sensations, on account of their diminutive nature, by which all that appertains to them is contracted. And this seems to be as agreeable to observation as to theory.
Case 4. All compound impressions A + B + C + D, &c. after sufficient repetition leave compound miniatures a + b + c + d, &c. which recur every now and then from slight causes, as well such as depend on association, as some which are different from it. Now, in these recurrences of compound miniatures, the parts are farther associated, and approach perpetually nearer to each other, agreeably to what was just now observed; i.e. the association becomes perpetually more close and intimate.
Case 5. When the ideas a, b, c, d, &c. have been sufficiently associated in any one or more of the foregoing ways, if we suppose any single idea of these, a for instance, to be raised by the tendency of the medullary substance that way, by the association of A with a foreign sensation or idea X or x, &c. this idea a, thus raised, will frequently bring in all the rest, b, c, d, &c. and so associate all of them together still farther.
And upon the whole, it may appear to the reader, that the simple ideas of sensation must run into clusters and combinations, by association; and that each of these will, at last, coalesce into one complex idea, by the approach and commixture of the several compounding parts.
It appears also from observation, that many of our intellectual ideas, such as those that belong to the heads of beauty, honour, moral qualities, &c. are, in fact, thus composed of parts, which, by degrees, coalesce into one complex idea.
And as this coalescence of simple ideas into complex ones is thus evinced, both by the foregoing theory, and by observation, so it may be illustrated, and farther confirmed, by the similar coalescence of letters into syllables and words, in which association is likewise a chief instrument. I shall mention some of the
