This passage of recognition, from the characteristic feeling of familiarity through the weaker of-course feeling into a sheer brain-habit or nervous set, illustrates the descending phase of a progression which is typical in psychology, and which is summed up in the =law of mental growth and decay=. We are constantly finding that a mental formation, a particular complex of mental processes, is at first thin and scant, then enriches itself by various supplementary processes, and then again thins out or tails off—finally, into mental nothingness; and recognition illustrates the downward half of the curve. The law was strongly insisted on by the late G. H. Lewes, an author who wrote largely on psychological topics, but who is better known to the general reader from his association with George Eliot. “This process,” Lewes tell us, “underlies all development. The voluntary actions become involuntary, the involuntary become automatic; the intelligent become habitual, and the habitual become instinctive. It is the same in the higher regions of intellect: the slow acquisitions of centuries of research become condensed into axioms which are intuitions.” We have already met the law in our discussions of attention and meaning; and we shall meet it again when we come to discuss action. § 40. =The Memory-Idea.=—But where, all this while, is the memory-image? If you had been asked, before you read the foregoing paragraphs, what happens when you recognise somebody or something, you would probably have replied, as the associationists reply: ‘The present sight of the object calls up an _image_ of that object, by the law of similarity; then the image or idea is compared with the perception, and the two are found to agree; and this agreement is what I mean by recognition.’ If it were then objected that observation fails to show any such idea or image, you would perhaps have said: ‘The whole thing takes place so quickly that the factors cannot ordinarily be distinguished; but all the same that is what must happen.’ And so you would have kept your faith in the image.