the " Edinburgh Review " : " There may be," says the reviewer, " Httle shakings in the brain, for anything we know, and there may even be shakings of a different kind accompanying every act of thought or perception ; — but that the shakings themselves are the thought or perception, we are so far from admitting, that we find it absolutely impossible to comprehend what is meant by tlie asser- tion. The shakings are certain throbbings, vibrations, or stirrings, in a whitish, half-fluid substance like custard, which we might see perhaps, or feel, if we had eyes and fingers sufficiently small or fine for the office. But what should we see or feel, upon the sup- position that we could detect by our senses, everything that actu- ally took place in the brain ? We should see the particles of this substance change their place a little, move a little up or down, to the right or the left, round about or zigzag, or in some other course or direction. This is all that Ave could see, if Dr. Hart- ley's conjecture were proved by actual observation ; because this is all that exists in motion, according to our conception of it, and all that we mean when we say that there is motion in any sub- stance. Is it intelligible, then, to say, that this motion, the whole of which we see and comprehend, is thought and feeling, and that thought and feeling will exist, wherever we can excite a simi- lar motion in a similar substance? — In our humble apprehension the proposition is not so much false, as utterly unmeaning and in- comprehensible." 1
If history repeats itself, so does philosophy. What the " Edin- burgh Review " said of Hartley nearly seventy years ago. Profes- sor Tyndall says of the Materialists of our day. " The passage from the physics of the brain to the corresponding facts of conscious- ness is unthinkable. Granted that a definite thought and a definite molecular action in the brain occur simultaneously ; we do not pos- sess the intellectual organ, nor apparently any rudiment of the organ, which would enable us to pass, by a process of reasoning, from the one phenomenon to the other. They appear together, but we do not know why. Were our minds and senses so expanded, strengthened, and illuminated, as to enable us to see and feel the very molecules of the brain ; were we capable of following all their motions, all their grouping, all their electric discharges, if oiich there be ; and were we intimately acquainted with the cor- responding states of thought and feeling, we should probably be as far as ever from the solution of the problem, How are these phys- ical processes connected with the facts of consciousness? The
1 Edinburgh Review, Oct. 1806, p. 157.
252 PART I. — THEOLOGY. [Ch. IH. — Anti-Theism.
chasm between the two classes of phenomena would still remain intellectually impassable. Let the consciousness of love, for exam- ple, be associated with a right-handed spiral motion of the mole- cules of the brain, and the consciousness of hate with a left-handed spiral motion. We should then know when we love that the mo- tion is in one dfrection, and when we hate that the motion is in the other, but the ' Why ? ' would still remain unanswered. In affirm- ing that the growth of the body is mechanical, and that thought, as exercised by us, has its correlative in the physics of the brain, I think the position of the ' Materialist ' is stated as far as that position is a tenable one. I think the Materialist will be able finally to maintain this position against all attacks ; but I do not think, as the human mind is at present constituted, that he can pass beyond it. I do not think he is entitled to say that his molecular grouping and his molecular motions explain everything. In reality they ex- plain nothing." ^
Priestley (1733-1804). Priestley owes his permanent reputation to his important discov- eries in tiie department of physical science. He was, however, prominent during his life for the part he took in philosophical and theological contreversies. Devoted to science, the senses M'ere for him the great sources of knowledge ; all others, except supernatural revelation which he admitted, he distrusted. He adopted with en- thusiasm the theory of Hartley which resolved thought and feeling into vibrations of the brain. Hartley, he said, had done more for the doctrine of mind than Newton accomplished for the theory of the material universe. He did not hesitate to avow himself a Ma- terialist. " Priestley," says Morell,^ " rested the truth of Mate- rialism upon two deductions. The first was, that thought and sensation are essentially the same thing — that the whole variety of our ideas, however abstract and refined they may become, are,
nevertheless, but modifications of the sensational faculty
The second deduction was, that all sensation, and, consequently, all thought, arises fi'om the affections of our material organization, and therefore consists entirel}^ in the motion of the material pal'ti- cles of which the nerves and brain are composed." He was a ne- cessitarian, and in morals a utilitarian. Believing, however, in God and in divine revelation, he ad nitted a future state of exist- ence. As the Bible teaches the doctrine of the resurrection of the
1 "Address before British Association," Aihenaum, for August 29, 1868. Quoted io Perowne's ffulsean Lectures, for 186?; Appendix, Note A.
2 Page 102.