The philosophy of the future will assuredly take more account than that of the past of the relation of thought and feeling to physical processes; and it may be that the qualities of the mind will be studied through the organism as we now study the character of a force through the affections of ordinary matter. We believe that every thought and every feeling has its definite mechanical correlative—that it is accompanied by a certain separation and remarshalling of the atoms of the brain. This latter process is purely physical; and were the faculties we now possess sufficiently strengthened, without the creation of any new faculty, it would doubtless be within the range of our augmented powers to infer from the molecular state of the brain the character of the thought acting on it, and conversely to infer from the thought the exact molecular condition of the brain. We do not say—and this, as will be seen, is all-important—that the inference here referred to would be an à priori one. But by observing, with the faculties we assume, the state of the brain and the associated mental affections, both might be so tabulated side by side that, if one were given, a mere reference to the table would declare the other. Our present powers, it is true, shrivel into nothingness when brought to bear on such a problem, but it is because of its complexity and our limits that this is the case. The quality of the problem and the quality of our powers are, we believe, so related, that a mere expansion of the latter would enable them to cope with the former. Why, then, in scientific speculation should we turn our eyes exclusively to the humble past? May it not be that a time is coming—ages no doubt distant, but still advancing—when the dwellers upon earth, starting from the gross human brain of to-day as a rudiment, may be able to apply to these mighty questions faculties of commensurate extent? Given the requisite expansibility to the present senses and intelligence of man—given also the time necessary for their expansion—and this high goal may be attained. Development is all that is required, and not a change of quality. There need be no absolute breach of continuity between us and our loftier brothers yet to come.
We have guarded ourselves against saying that the inferring of thought from material combinations and arrangements would be an inference à priori. The inference meant would be the same in kind as that which the observation of the effects of food and drink upon the mind would enable us to make, differing only from the latter in the degree of analytical insight which we suppose attained. Given the masses and distances of the planets, we can infer the perturbations consequent on their mutual attractions. Given the nature of a disturbance in water, air, or ether—from the physical qualities of the medium we can infer how its particles will be affected. Here the mind runs with certainty along the line of thought which connects the phenomena, and from beginning to end finds no break in the chain. But when we endeavour to pass by a similar process from the phenomena of physics to those of thought, we meet a problem which transcends any conceivable expansion of the powers which we now possess. We may think over the subject again and again, but it eludes all intellectual presentation. We stand at length face to face with the Incomprehensible. The territory of physics is wide, but it has its limits from which we look with vacant gaze into the region beyond. Whence come we; whither go we? The question dies without an answer—without even an echo—upon the infinite shores of the Unknown. Let us follow matter to its utmost bounds; let us claim it in all its forms to experiment with and to speculate upon. Casting the term ‘vital force’ from our vocabulary, let us reduce, if we can, the visible phenomena of life to mechanical attractions and repulsions. Having thus exhausted physics, and reached its very rim, the real mystery still looms beyond us. We have, in fact, made no step towards its solution. And thus it will ever loom—ever beyond the bourne of knowledge—compelling the philosophies of successive ages to confess that
We are such stuff
As dreams are made of, and our little life
Is rounded with a sleep.
FOOTNOTES:
[1] One of my critics remarks, that he does not see the wit of calling Goethe’s ‘Farbenlehre’ and Bain’s ‘Logic,’ ‘two volumes of poetry.’ Nor do I.
[2] Induction, page 422.
[3] This glass, by reflected light, had a colour ‘strongly resembling that of a decoction of horse-chestnut bark.’ Curiously enough Goethe refers to this very decoction:—‘Man nehme einen Streifen frischer Rinde von der Rosskastanie, man stecke denselben in ein Glas Wasser, und in der kürzesten Zeit werden wir das vollkommenste Himmelblau entstehen sehen.’—Goethe’s Werke, b. xxix. p. 24.
[4] A resolute scrutiny of the experiments, recently executed with reference to this question, is sure to yield instructive results.