§. 5. The memory also is a faculty whose nature is as obscure, and hath as much of riddle in it as any of the Former: it seems to be an organical power, because bodily distempers often mar its ideas, and cause a total oblivion: but what instruments the soul useth in her review of past impressions, is a question which may drive enquiry to despair. There are four principal hypotheses by which a resolution hath been attempted.
The Peripatetic, the Cartesian, the Digbean, and the Hobbian. We'll examine these accounts of the Magnale. And I begin with that which will needs have itself believed the most venerable for antiquity and worth.
(i) then according to Aristotle and his Peripatum, objects are conserved in the memory by certain intentional species, beings, which have nothing of matter in their essential constitution, but yet have a necessary subjective dependence on it, whence they are called material. To this briefly.
Besides that these species are made a medium between body and spirit, and therefore partake of no more of being, than what the charity of our imaginations affords them; and that the supposition infers a creative energy in the object their producent, which philosophy allows not to creature-efficients; I say, beside these, it is quite against their nature to subsist, but in the presence and under the actual influence of their cause; as being produced by an emanative causality, the effects whereof die in the removal of their origin. But this superannuated conceit deserves no more of our remembrance, than it contributes to the apprehension of it. And theresore I pass on to the Cartesian which speaks thus:
The glandula pinealis, in this philosophy made the seat of common sense, doth by its motion impel the spirits into divers parts of the brain; till it find those wherein are some tracks of the object we would remember; which consists in this, viz. That the pores of the brain, through which the spirits before took their course, are more easily opened to the spirits which demand re-entrance; so that finding those pores, they make their way through them sooner than through others: whence there ariseth a special motion in the glandula, which signifies this to be the object we would remember.
But I fear there is no security neither in this hypothesis; for if memory be made by the easy motion of the spirits through the opened passages, according to what hath been noted from Descartes; whence have we a distinct remembrance of such diversity of objects, whose images without doubt pass through the same apertures? And how should we recal the distances of bodies which lie in a line? Or, is it not likely, that the impelled spirits might light upon other pores accommodated to their purpose, by the motion of other bodies through them? Yea, in such a pervious substance as the brain, they might find an easy either entrance, or exit, almost everywhere; and therefore to shake every grain of corn through the same holes of a sieve in repeated winnowings, is as easy to be performed, as this to be perceived. Besides, it's difficult to apprehend, but that these avenues should in a short time be stopped up by the pressure of other parts of the matter, through its natural gravity, or other alterations made in the brain: and the opening of other vicine passages might quickly obliterate any tracks of these; as the making of one hole in the yielding mud, defaces the print of another near it; at least the accession of enlargement, which was derived from such transitions, would be as soon lost, as made.
We are still to seek then for an Oedipus for the riddle; wherefore we turn our eyes to the Digbean account, of which this is the sum; that things are reserved in the memory by some corporeal exuviae and material images; which having impinged on the common sense, rebound thence into some vacant cells of the brain, where they keep their ranks and postures in the same order that they entred, till they are again stirred up; and then they slide through the fancy, as when they were first presented.
But, how is it imaginable, that those active particles which have no cement to unite them, nothing to keep them in the order they were set, yea, which are ever and anon jostled by the occursion of other bodies, whereof there is an infinite store in this repository, should so orderly keep their cells without any alteration of their site or posture, which at first was allotted them? And how is it conceivable, but that carelesly turning over the ideas of our mind to recover something we would remember, we should put all the other images into a disorderly floating, and so raise a little chaos of confusion, where nature requires the exactest order. According to this account, I cannot see, but that our memories would be more confused than our midnight compositions: for is it likely, that the divided atomes which presented themselves together, should keep the same ranks in such a variety of tumultuary agitations, as happen in that liquid medium? An heap of ants on an hillock will more easily be kept to an uniformity in motion; and the little bodies which are incessantly playing up and down the air in their careless postures, are as capable of regularity as these.
The last account of the faculty we are inquiring of is the Hobbian, according to which hypothesis; memory is nothing else but the knowledge of decaying sense, made by the reaction of one body against another; or as the author expresses it in his Human Nature, a missing of parts in an object. The foundation of which principle (as of many of its fellows) is totally reversed by the most ingenious commentator upon immaterial beings, Dr. H. More in his book Of Immortality. I shall therefore leave that cause in the hands of that most learned undertaker, and only observe two things to my present purpose. (i) neither the brain, nor spirits, nor any other material substance within the head can for any considerable space of time conserve motion. The former is of such a clammy consistency, that it can no more retain it than a quagmire: and the spirits for their liquidity are more uncapable than the fluid medium, which is the conveyer of sounds, to persevere in the continued repetition of vocal airs. And if there were any other substance within us, as fitly tempered to preserve motion, as the author of the opinion could desire: yet (2) which will equally press against either of the former, this motion would be quickly deadened by counter-motions; and we should not remember anything, but till the next impression. Much less can this principle give an account, how such an abundance of motions should orderly succeed one another, as things do in our memories: and to remember a song or tune, it will be required, that our souls be an harmony more than in a metaphor, continually running over in a silent whisper those musical accents which our retentive faculty is preserver of. Which could we suppose in a single instance; yet a multitude of musical consonancies would be as impossible, as to play a thousand tunes on a lute at once. One motion would cross and destroy another; all would be clashing and discord: and the musician's soul would be the most disharmonious: for, according to the tenor of this opinion, our memories will be stored with infinite variety of divers, yea contrary motions, which must needs interfere, thwart, and obstruct one another: and there would be nothing within us, but ataxy and disorder.
§. 6. Much snore might be added of the difficulties, which occur concerning the understanding, pliancy, will, and affections. But the controversies hereabout, are so hotly managed by the divided schools, and so voluminously everywhere handled; that it will be thought better to say nothing of them, than a little. The sole difficulties about the will, its nature, and sequency to the understanding, &c. have almost quite baffled inquiry, and shown us little else, but that our understandings are as blind as it is. And the grand question depending hereon, Ποθεν το κακον[Greek: Pothen to kakon]; I think will not be ended, but by the final abolition of its object. They, that would lose their knowledge here, let them diligently inquire after it. Search will discover that ignorance, which is as invincible, as its cause. These controversies, like some rivers, the further they run, the more they are hid. And it may be a poorer account is given to them now, than some centuries past, when they were a subject of debate to the pious fathers.