Hamilton says: "When suddenly awakened during sleep (and to ascertain the fact I have caused myself to be roused at different seasons of the {440} night), I have always been able to observe that I was in the middle of a dream;" but adds, "that he was often scarcely certain of more than the fact that he was not awakened from an unconscious state, and that we are often not able to recollect our dreams." He gives, as the peculiarity of somnambulism, that we have no recollection when we awake of what has occurred during its continuance.(Vol.I.P.320-322.) Every one will admit that we are often conscious of states at the time, which we either cannot remember at all, or (what will equally serve our purpose) more probably cannot remember, except for a very brief period after we have experienced them.We have thus an established order of facts competent to explain the whole phenomenon without resorting to a Leibnitzian doctrine, which has been applied by certain later German pantheists to show how existence may rise gradually from deadness to life, and from unconsciousness to consciousness.
Under the head of the reproductive faculties he has two profound lectures on the Association of Ideas.In the close of his edition of Reid there is a learned disquisition on the well-known passage of Aristotle, in which he gives, with his usual brevity, a classification of.laws which regulate the train of our thoughts.Hamilton so interprets that passage as to make Aristotle announce one generic law and three special ones.I am unwilling to set my authority against so accurate a scholar as Hamilton -- , but I have often looked into that passage, and can find no evidence of Aristotle having resolved all into one law.In the same note Hamilton had begun to expound his own theory, but broke off, and closed the book in the middle of a sentence.Most readers will feel that the account given in these lectures, though somewhat fuller, is far too brief, and illustrated by too few examples to be easily understood.His pupils could not be more profitably employed than in fully unfolding the doctrine of their master on this subject, and applying it to explain the well-known phenomena.He thinks that the whole facts can be explained by one great law, which he calls the law of redintegration, which he finds incidentally expressed by Augustine.This law may be thus enounced, -- "Those thoughts suggest each other which had previously constituted parts of the same entire or total act of cognition." (Vol.
II.p.238.) He again quotes Schmid Thus {441} the supreme law of association, -- that activities excite each other in proportion as they have previously belonged as parts to one whole activity, -- is explained from the still more universal principle of the unity of all our mental energies in general." (P.241.) I am inclined to look on this as, on the whole, the most philosophical account which has been given of the law of association.It at once explains the cases of simple repetition in which one link of a chain of ideas which had previously passed through the mind, being caught, all the rest come after; as when we have got the first line of a poem committed to memory, and the others follow in order.It easily explains, too, all cases in which we have had a variety of objects before us in one concrete act, -- thus if we have passed along a particular road, with a certain person, observing the mountain or river in front, and talking on certain objects, -- we find that when any one of these recurs it is apt to suggest the others.It is thus if we have often heard in youth the cry of a particular animal, goose or grouse, turkey or curlew, the cry will ever bring up afresh the scenes of our childhood.It is more doubtful whether the law can explain a third class of cases when it is not the same which suggests the same, but an object suggests another object which has never been individually associated with it, but is like it, or is otherwise correlated with it; as when the conqueror Alexander suggests Julius Caesar or Bonaparte.It needs an explanation to show how the law can cover such a case, which, however, I rather think it can, though I am by no means inclined to admit the explanations of the Hamiltonians proceeding on their narrow and peculiar view of correlates.
IV.This leads us to refer to the next faculty, -- the Elaborative, equal to Comparison, -- that is the Faculty of Relations.The phrase elaborative is an expressive epithet, but is not a good special denomination, as there is elaboration in other exercises as well as in this.
Comparison, or the correlative faculties, or the faculties of relation, is the better epithet.Under this head he has some learned and acute remarks on the abstract and the general notion, and on language, and is terribly severe, as usual, on Dr.Thomas Brown.I am of opinion that Brown's views on this subject are, in one or two points, more enlarged than those of Hamilton himself, who has over {442}