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must be acknowledged concerning the other;"* and he is so confident of the truth of this maxim, that he makes it one of the pillars of his philosophy To those who may be inclined to admit this maxim on his authority, I would propose a few plain questions. Do you feel any, even the least, warmth in the idea of a bonfire, a burning mountain, or the general conflagration? Do you feel more real cold in Virgil's Scythian winter than in Milton's description of the flames of hell? Do you acknowledge that to be true of the idea of eating, which is certainly true of the impression of it, that it alleviates hunger, fills the belly, and contributes to the support of human life? If you answer these questions in the negative, you deny one of the fundamental principles of this philosophy. We have, it is true, a livelier perception of a friend when we see him, than when we think of him in his absence: but this is not all: every person of a sound mind knows, that in the one case we believe, and are certain, that the object exists, and is present with us; in the other we believe, and are certain, that the object is not present: which, however, they must deny who maintain that an idea differs from an impression only in being weaker, and in no other respect whatsoever.

"That every idea should be a copy and resemblance of the impression whence it is derived ;-that, for example, the idea of red should be a red idea; the idea of a roaring lion a roaring idea; the idea of an ass, a hairy, longeared, sluggish idea, patient of labour, and much addicted to thistles; that the idea of extension should be extended, and that of solidity solid;-that a thought of the mind should be endued with all, or any, of the qualities of matter;-is, in my judgment, inconceivable and impossible. Yet our author takes it for granted; and it is another of his fundamental maxims. Such is the credulity of skepticism!"

It is a singular coincidence, that while the substantive existence of an external world was thus hotly attacked by metaphysics, the science of physics should have proved just as adverse to it; thus reviving, as we have already seen, the very same double assault to which it had been exposed at Athens, shortly after the establishment of the Academy. This latter controversy commenced and hinged upon what are the real qualities of matter. Heat, cold, colours, smell, taste, and sounds had been pretty generally banished from the list about the middle of the seventeenth century. Locke contended, after Sir Isaac Newton, for solidity, extension, mobility, and figure: but it was soon found that there is a great difficulty in granting it solidity: that the particles of bodies never come into actual contact, or influence each other by the means of objective pressure; that however apparently solid the mass to which they belong, such mass may be reduced to a smaller bulk by cold, as it may be increased in bulk by heat; that we can hence form no conception of perfect solidity, and every fact in nature appears to disprove its existence. The minutest corpuscle we can pick out is capable of a minuter division, and the parts into which it divides possessing the common nature of the corpuscle which has produced them, must necessarily be capable of a still farther division; and, as such divisions can have no assignable limit, matter must necessarily and essentially be divisible to infinity. For these and similar reasons M. Boscovich contended that there is no such thing as solidity in matter; nor any thing more than simple, unextended, indivisible points, possessing the powers of attraction and repulsion, yet producing extension by their combination.t

Upon the self-contradiction of this hypothesis I have found it necessary to comment on a former occasion ; and shall now, therefore, only farther observe, that it just as completely sweeps the whole of matter away with a physical broom, as the systems of Berkeley and Hume do with a metaphysical; for, by leaving us nothing but unextended points, possessing mere powers without a substrate, it leaves nothing at all,-a world, indeed, but a

Treatise on Human Nature, vol. i. p. 41.

†Theoria Philosophia Naturalis, Vien. 1758. Series 1. Lecture iii. See also Dr. Wollaston's paper "On the finite Extent of the Atmosphere," Phil. Trans. 1822, p. 89.

A a

world" without form, and void;” with darkness, not only upon the face of the deep, but there and every where else.

"That nothing," says Dr. Reid, "can act immediately where it is not, I think must be admitted; for I think, with Sir Isaac Newton, that power without substance is inconceivable." Lord Kames, however, in his Elements of Criticism, though a strong advocate for the common-sense system, expresses his doubts of the doctrine contained in this passage.

To complete the folly of the age, and fix the laugh of the simple against the wise, while Berkeley, Hume, and Boscovich were thus, in their different ways, dissipating the world of matter, in favour of the world of mind, another set of philosophers started up,-

-impios

Titanas, immanemque turinam,"

An impious, earth-born, fierce, Titanic race,

and put to flight the world of mind in favour of the world of matter. Hobbes, who was a contemporary and friend of Des Cartes, courageously led the van, and did ample justice, and somewhat more than ample justice, to the senses, by contending that we have no other knowledge than what they supply us with, and what they themselves derive from the world before them; that the mind is nothing more than the general result of their action; and that with them it begins, and with them it ceases.

To Hobbes succeeded Spinosa, who was born in the very same year with Locke, and who carried forward the crusade of matter against mind, to so illimitable a career, that he made the world, the human senses, the human soul, and the Deity himself, matter and nothing else: all one common material being; no part of which can or ever could exist otherwise than as it is, and consequently every part of which is equally the creature and the Creator. In the midst of these indiscriminate assaults appeared Hartley, whose learning, benevolence, and piety entitle his memory to be held in veneration by every good man. He strenuously contended for the existence of mind and matter as distinct principles; and conceived it was in his power to settle the general controversy, by showing what Locke had failed to do, or rather what he had too much modesty to attempt, the direct means by which the external senses, and consequently the external world, operate upon the mind. And hence arose the well-known and at one time highly popular hypothesis of the association of ideas. It was conceived by Dr. Hartley that the nervous fibrils, which form the medium of communication between the external senses and the brain or sensory, are solid and elastic capillaments, that on every impression of objects upon the senses the nervous chord, immediately connected with the sense, vibrates through its whole length, and communicates the vibration to the substance of the brain, and particularly to its central region, which is the seat of sensation, leaving upon every communication a mark or vestige of itself; which produces a sensation, and excites its correspondent perception or idea. The more frequently these vibrations are renewed, or the more vigorously they are impressed, the stronger will be the vestiges or ideas they induce; and as, in every instance, they occasion vibratiuncles, or miniature vibrations, through the substance of the brain itself, a foundation is hereby laid for a series of slighter vestiges, sensations, and ideas after the primary vibrations have ceased to act. And hence originate the faculties of memory and imagination. And as any order of vibra tions, by being associated together a certain number of times, obtain a habit of mutual influence, any single sensation or single idea belonging to such order acquires a power of calling the whole train into action, either synchro⚫ nously or successively, whenever called into action itself.

Now, according to this system, the brain of man is a direct sensitive violin, consisting of musical strings, whose tones go off in thirds, fifths, and eighths,

Hor. lib. iii. 4.

as regularly as in a common fiddle, through the whole extent of its diapason; and the orator who understands his art, may be said, without a figure, to play skilfully upon the brains of his auditors. The hypothesis, however, is ingenious and elegant, and has furnished us with a variety of detached hints of great value; but it labours under the following fatal objections: First, the nervous fibres have little or no elasticity belonging to them, less so perhaps than any other animal fibres whatever; and next, while it supposes a soul distinct from the brain, it leaves it no office to perform: for the medullary vibrations are not merely causes of sensations, ideas, and associations, but in fact the sources of reason, belief, imagination, mental passion, and all other intellectual operations whatever.

Admitting, therefore, the full extent of this hypothesis, still it gives us no information about the nature of the mind and its proper functions; and leaves us just as ignorant as ever of the power by which it perceives the qualities of external objects. The difficulty was felt by many of the advocates for the associate system, especially by Priestley and Darwin; and it was no sooner felt than it was courageously attacked, and in their opinion completely overcome. Nothing was clearer to them than that Dr. Hartley had overloaded his system with machinery: that no such thing as a mind was wanting distinct from the brain or sensory itself: that ideas, to adopt the language of Darwin, are the actual contractions, motions, or configurations of the fibres which constitute the immediate organ of sense, and consequently material things;* or, to adopt the language of Priestley, that ideas are just as divisible as the archetypes or external objects that produce them; and, consequently, like other parts of the material frame, may be dissected, dried, pickled, and packed up, like herrings, for home-consumption or exportation, according as the foreign or domestic market may have the largest demand for them. And consequently, also, that the brain or censory, or the train of material ideas that issue from it, is the soul itself; not a fine-spun flimsy immaterial soul or principle of thought, like that of Berkeley or even of Hume, existing unconnectedly in the vast solitude of universal space, but a solid, substantial, alderman-like soul, a real spirit of animation, fond of good cheer and good company; that enters into all the pursuits of the body while alive, and partakes of one common fate in its dissolution.

If there be too much crassitude in this modification of materialism, as has generally been supposed, even by materialists themselves, there is at least something tangible in it: something that we can grasp and cope with, and fix and understand; which is more, I fear, than can be said of those subtle and more complicated modifications of the same substrate, which have somewhat more lately been brought forward in France to supply its place, and which represent the human fabric as a duad, or even a triad of unities, instead of a mixed or simple unity; as a combination of a corruptible life within a corruptible life two or three deep, each possessing its own separate faculties or manifestations, but covered with a common outside.

This remark more especially applies to the philosophers of the French school; and particularly to the system of Dumas‡, as modified by Bichat: under which more finished form man is declared to consist of a pair of lives, each distinct and coexistent, under the names of an organic and an animal life; with two distinct assortments of sensibilities, an unconscious and a conscious. Each of these lives is limited to a separate set of organs, runs its race in parallel steps with the other; commencing coetaneously and perishing at the same moment. This work appeared at the close of the past century; was read and admired by most physiologists; credited by many; and became the popular production of the day. Within ten or twelve years, however, it ran its course, and was as generally either rejected or forgotten even in France; and M. Richerand first, and M. Magendie since, have thought themselves called upon to modify Bichat, in order to render him more palatable, as Bichat had already modified Dumas. Under the last series

Zoon. vol. i. p. 11, edit. 3

Principes de Physiologie, tom. iv. 8vo. Paris, 1800-3.

† Study of Med. vol. iv. p 41-45, edit. 2. Recherches sur la Vie et la Mort, &c.

of remodelling, which is that of M. Magendie, we have certainly an im provement, though the machinery is quite as complex. Instead of two distinct lives M. Magendie presents us with two distinct sets or systems of action or relation, each of which has its separate and peculiar_functions, a system of nutritive action or relation, and a system of vital. To which is added, by way of appendix, another system, comprising the functions of generation. Here, however, the brain is not only the seat but the organized substance of the mental powers: so that, we are expressly told, a man must be as he is made in his brain, and that education, and even logic itself, is of no use to him. "There are," says M. Magendie, "justly celebrated persons who have thought differently; but they have hereby fallen into grave errors." A Deity, however, is allowed to exist, because, adds the writer, it is comfortable to think that he exists, and on this account the physiologist cannot doubt of his being. "L'intelligence de l'homme," says he," se compose de phénoménes tellement différens de tout ce que présente d'ailleurs la nature, qu'on les rapporte à un être particuliere qu'on regarde comme une emanation de la Divinité. Il est trop consolant de croire à cet être, pour que le physiologiste métte en doute son existence; mais la séverité de langage ou de logique que comporte maintenant la physiologie exige que l'on traite de l'intelligence humaine comme si elle était le résultat de l'action d'un organe. En s'écartant de cette marche, des hommes justement célèbres sont tombés dans des graves erreurs; en la suivant, on a, d'ailleurs, le grand avantage de conserver la même méthode d'étude, et de rendre trés faciles des choses qui sont envisagées généralement comme presqu' au-dessus de l'esprit humain."—"Il existe une science dont le but est, d'apprendre à raisonner justement: c'est la logique: mais le jugement erroné où l'esprit faux (for judgment, genius, and imagination, and therefore false reasoning, all depend on organization) tiennent à l'organization. Il est impossible de se changer à cet egard; nous restons, tels que la nature nous à faits."

Dr. Spurzheim has generally been considered, from the concurrent tenor of his doctrines, as belonging to the class of materialists; but this is to mistake his own positive assertion upon the subject, or to conclude in opposition to it. He speaks, indeed, upon this topic with a singular hesitation and reserve, more so, perhaps, than upon any other point whatever; but as far as he chooses to express himself on so abstruse à subject, he regards the soul as a distinct being from the body, and at least intimates that it may be nearer akin to the Deity. Man is with him also possessed of two lives, an AUTOMATIC and ANIMAL: the first produced by organization alone, and destitute of consciousness; the second possessed of consciousness dependent on the soul, and merely manifesting itself by organization. "We do not," says he, "attempt to explain how the body and soul are joined together and exercise a mutual influence. We do not examine what the soul can do without the body. Souls, so far as we know, may be united to bodies at the moment of conception or afterward; they may be different in all individuals, or of the same kind in every one; they may be emanations from God, or something essentially different." The mind of this celebrated craniologist seems to be wonderfully skeptical and bewildered upon the subject, and studiously avoids the important question of the capacity of the soul for an independent and future existence; but with the above declaration he cannot well be arranged in the class of materialists.

The hypothesis which has lately been started by Mr. Lawrence is altogether of a different kind, and though undoubtedly much simpler than any of the preceding, does not seem to be built on a more stable foundation. According to his view of the subject, organized differs from inorganized matter merely by the addition of certain PROPERTIES which are called vital, as sensibility and irritability. Masses of matter endowed with these new PROPERTIES become organs and systems of organs, constitute an animal frame, and exe

Précis Elementaire de Physiologie, tom. ii. 8vo. Paris, 1816, 1817. + Précis Elementaire, &c. ut supra, passim. Physiognomical System, &c. p. 253, 8vo. Lond. 1815 Introduction to Comparative Anatomy and Physiology, &c. 8vo. 1816.

cute distinct sets of PURPOSES OF FUNCTIONS; for functions and purposes carried into execution are here synonymous. "Life is the assemblage of ALL the functions (or purposes), and the general result of their exercise."*

Life, therefore, upon this hypothesis, instead of being a twofold or threefold reality, running in a combined stream, or in parallel lines, has no reality whatever. It has no ESSE or independent existence. It is a mere assemblage of PURPOSES, and accidental or temporary PROPERTIES: a series of phenomena,† as Mr. Lawrence has himself correctly expressed it ;-a name without a thing. "We know not," says he, "the nature of the link that unites these phenomena, though we are sensible that a connexion must exist; and this conviction is sufficient to induce us to give it a NAME, which the VULGAR regard as the sign of a particular principle; though in fact that name can only indicate the ASSEMBLAGE OF THE PHENOMENA which have occasioned its formation."

The human frame is, hence, a barrel-organ, possessing a systematic arrangement of parts, played upon by peculiar powers, and executing particular pieces or purposes; and life is the music produced by the general assemblage or result of the harmonious action. So long as either the vital or mechanical instrument is duly wound up by a regular supply of food, or of the wince, so long the music will continue: but both are worn out by their own action; and when the machine will no longer work, the life has the same close as the music; and in the language of Cornelius Gallus as quoted and appropriated by Leo. X.,

redit in nihilum, quod fuit ante nihil.

There is, however, nothing new either in this hypothesis or in the present explanation of it. It was first started in the days of Aristotle by Aristoxenus, a pupil of his, who was admirably skilled in music, and by profession a physician. It was propounded to the world under the name of the system of HARMONY, either from the author's fondness for music, or from his comparing the human frame to a musical instrument, and his regarding life as the result of all its parts acting in accordance, and producing a general and harmonious effect.

We have already had occasion to notice this hypothesis in a former lecture, and the triumphant objections with which it was met by the Stoics as well as by the Epicureans; as also that it has at times been revived since, and especially by M. Lusac, who extended it to even a wider range: while the same objections remain unanswered to the present hour, and seem to be altogether unanswerable.

There is, moreover, the same looseness in the term PHENOMENA, employed by Mr. Lawrence and the French writers just adverted to, as we have remarked in many of the opposers of Mr. Locke, who seem to be afraid of fettering themselves with definite terms or definite ideas. This looseness may be convenient in many cases, but it always betrays weakness or imprecision. In the mouth of the Platonists and Peripatetics of ancient Greece, we distinctly know that the term phenomena denoted the archetypes of the one, or the phantasms of the other. We understand it with equal clearness as made use of, though in very different senses, by Leibnitz in reference to his system of PRE-ESTABLISHED HARMONY, and by Professor Robson, in reference to that of Boscovich. But when M. Magendie, or Mr. Lawrence, tells us that "human intelligence," which is the phrase of the former, in the passage just quoted, or "life," which is that of the latter, is a COMPOSITION OF ASSEMBLAGE of PHENOMENA, a "RESULT OF THE ACTION of an organ,"-we have no distinct notion whatever put before us. The "purposes," or "properties," or "functions," or whatever it is they intend under the name of PHENOMENA, certainly do not seem to be strictly material in themselves, though we are told they are, in some way or other, the product of a material organ: but whether they be the

* Introduction to Comparative Anatomy and Physiology, &c. 8vo. p. 120, 1816. Ibid.

Study of Med. ut supra.

† Ibid. p. 122. Series 1. Lect. ix. on the Principle of Life.

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