The pseudo-philosophers of our time have bewildered the public mind by the wild flights of their imagination; thought, the so-called spiritual attributes of man, are merely a function of brain protoplasm; the brain, say they, secretes thought, just as the liver secretes bile, or as oxygen and sulphur produce sulphuric acid, and all the varied phenomena of nature are nothing more than the molecular changes of matter; the operations of the mind are but the products of the caudate cells of the brain, and volition and consciousness are mere physical manifestations. They see only the physio-chemical side of nature, they utterly ignore any spiritual attribute in man, they regard metaphysics as a relic of mediæval superstition, and they assert that all mental operations are bodily functions, and simply the result of some molecular or atomic change in the brain; indeed, the German philosophers go so far as to say that life itself is only a "special and most complicated act of mechanics;"[30] that there is no real distinction between living and dead matter, and that vitality is a metaphysical ghost (ein metaphysisches Gespenst).[31]

At the International Psychological Congress held in Paris, in 1878, at which it was my privilege to be present, Professor Mierzejewski, of St. Petersburg, laid before the congress the result of his elaborate experiments on the brains of idiots, his communication being illustrated by casts of the brains of idiots, and also of certain animals, and the learned Russian professor's conclusions strongly militated against the theories of the philosophers of whom I have been speaking.

In order to understand the great value and import of Dr. Mierzejewski's investigations, I must remind you that the human brain is composed of two kinds of nerve structure, of an essentially different nature, grey matter and white matter. Examined microscopically, the grey matter is found to be composed of cells, while the white matter consists of fibres; their function also is different, the former being regarded as the generator of nerve force, while the latter simply serves as the medium by which this force is transmitted. As the manifestation of the intellectual powers is supposed to be in some way connected with the development of the grey matter of the cerebral convolutions, one would expect to find in idiots a deficiency of this element of brain tissue.[32] Dr. Mierzejewski maintained that this is by no means the case, and he mentioned an instance of an idiot in whose brain the surface of grey matter was enormous. So it would seem that there is no fixed relation between the amount of grey matter of the brain and intellectual power, for richness of grey substance and abundance of nerve cells may be accompanied by idiocy.

Now, as these startling statements of the Russian professor were not made in a hole and corner, but were enunciated in the presence of leading psychologists from all parts of the world, I felt myself justified in telling the materialists that they must be faced, and either answered or admitted as correct; and as my comments upon these experiments were subsequently published in a leading London periodical and widely circulated, I am now justified in assuming that the inferences I then drew from these remarkable experiments cannot be controverted, and that the time has not yet arrived when the broad distinctions between mind and matter are to be obliterated, and man reduced to a mere automaton, a creature of a blind necessity.

Without unduly exaggerating the importance of Dr. Mierzejewski's experiments, it must be admitted that very great interest attaches to them at this juncture, when attention is so widely directed to the mysterious connection between matter and mind. Unhappily, instead of solving the question, the Russian professor's researches tend to shroud it in a still deeper mystery, and show that what has been termed the "slippery force of thought—the vis vivida animæ"—cannot be weighed in the balance; and they fully justify the eloquent language of a recent writer when he says, "Far more transcendent than all the glories of the universe is the mind of man. Mind is indeed an enigma, the solution of which is apparently beyond the reach of this very mind, itself the problem, the demonstrator, the demonstration, and the demonstrants ."

Those who maintain that the brain is the organ of the mind, do not tell us what we are to understand by organ, brain, or mind; they seem to me to confound two things, the one with the other. In fact, they make no distinction between thought, mind, consciousness, and the instrument by which these attributes become externally manifested. It is true, we have no evidence to show that the mind can operate independently of the nervous system; on the contrary, all physiological data bearing upon the question of this mutual relation, go to prove that where there is no nervous system there are no mental manifestations. Moreover, as G.H. Lewes says, "It is the man, and not the brain, that thinks: it is the organism as a whole, and not one organ, that feels and acts."[33]

Every faculty manifests itself by means of matter, but it is important not to confound the faculty with the corporeal organ upon which the external manifestation of such faculty depends. The word organ is the name given to a part of the human frame by which we have sensation, and by means of which we do a certain act or work; such are the organs of sight, sound, smell, taste, and touch. All these organs are passive, and require to be operated on ab extra, precisely in the same way as the musical organ, which is an instrument constructed by man, requires man's interference for the production of musical sounds.

When a musician sits down to a piano, the music cannot be said to be in the instrument, but in the soul of the performer. If the instrument be in good order, the inspiration of a Thalberg or of a Liszt will become apparent; break the cords or otherwise damage the instrument, and nothing but discordant strains are produced, the musical faculty of the performer, however, remaining unaffected. We are all familiar with Plato's celebrated dialogue on the Immortality of the Soul, where a disputant with Socrates inquires if the soul is not like the harmony of a lyre, more beautiful, more divine than the lyre itself, but yet is nothing without the lyre, vanishing when this instrument is broken.

Let me further illustrate this point by an allusion to the electric telegraph, by means of which ideas and words are transmitted from mind to mind with a rapidity to which ordinary language cannot attain. Now, the electrical battery may be not inaptly compared to the brain, and the telegraph wires to the nerves