a theist? The mystery of existence and the inconceivability of matter thinking are their common data. Upon these data the materialist, justly arguing that he has no right to make his own conceptive faculty the unconditional test of objective possibility, is content to merge the mystery of his own mind's existence into that of Existence in general; while the theist, compelled to accept without explanation the mystery of Existence in general, nevertheless has recourse to inventing a wholly gratuitous hypothesis to explain one mode of existence in particular. If it is said that the latter hypothesis has the merit of causing the mystery of material existence and the mystery of mental existence to be united in a thinkable manner—viz., in a self-existing Mind,—I reply, It is not so; for in whatever degree it is unthinkable that Matter should be the cause of Mind, in that precise degree must it be unthinkable that Mind was ever the cause of Matter, the correlatives being in each case the same, and experience affording no evidence of causality in either.

§ 14. The two hypotheses, therefore, are of exactly equivalent value, save that while the one has a certain basis of fact to rest upon,^[7] the other is wholly arbitrary. But it may still be retorted, 'Is not that which is most conceivable most likely to be true? and if it is more conceivable that my intelligence is caused by another Intelligence than that it is caused by Non-intelligence, may I not regard the more conceivable hypothesis as also the more probable one? It is somewhat difficult to say how far this argument is, in this case, valid; only I think it is quite evident that its validity is open to grave dispute. For nothing can be more evident to a philosophical thinker than that the substance of Mind must—so far at least as we can at present see—necessarily be unknowable; so that if Matter (and Force) be this substance, we should antecedently expect to find that the actual causal connection should, in this particular case, be more inconceivable than some imaginary one: it would be more natural for the mind to infer that something conceivably more akin to itself should be its cause, than that this cause should be the entity which really gives rise to the unthinkable connection. But even waiving this reflection, and granting that the above argument is valid, it is still to an indefinite degree valueless, seeing that we are unable to tell how much it is more likely that the more conceivable should here be true than that the less conceivable should be so.

§ 15. Returning then to Locke's comparison between the certainty of this argument and that which proves the sum of the angles of a triangle to be equal to two right-angles, I should say that there is a virtual, though not a formal, fallacy in his presentation. For mathematical science being confessedly but of relative significance, any comparison between the degree of certainty attained by reasoning upon so transcendental a subject as the present, and that of mathematical demonstrations regarding relative truth, must be misleading. In the present instance, the whole strain of the argument comes upon the adequacy of the proposed test of truth, viz., our being able to conceive it if true. Now, will any one undertake to say that this test of truth is of equivalent value when it is applied to a triangle and when it is applied to the Deity. In the one case we are dealing with a geometrical figure of an exceedingly simple type, with which our experience is well acquainted, and presenting a very limited number of relations for us to contemplate. In the other case we are endeavouring to deal with the summum genus of all mystery, with reference to which experience is quite impossible, and which in its mention contains all the relations that are to us unknown and unknowable. Here, then, is the oversight. Because men find conceivability a valid test of truth in the affairs of everyday life—as it is easy to show à priori that it must be, if our experience has been formed under a given code of constant and general laws—therefore they conclude that it must be equally valid wherever it is applied; forgetting that its validity must perforce decrease in proportion to the distance at which the test is applied from the sphere of experience.^[8]

§ 16. Upon the whole, then, I think it is transparently obvious that the mere fact of our being unable to conceive, say, how any disposition of matter and motion could possibly give rise to a self-conscious intelligence, in no wise warrants us in concluding that for this reason no such disposition is possible. The only question would appear to be, whether the test which is here proposed as an unconditional criterion of truth should be allowed any the smallest degree of credit. Seeing, on the one hand, how very fallible the test in question is known to have proved itself in many cases of much less speculative difficulty—seeing, too, that even now "the philosophy of the condition proves that things there are which may, nay must, be true, of which nevertheless the mind is unable to construe to itself the possibility;"^[9] and seeing, on the other hand, that the substance of Mind, whatever it is, must necessarily be unknowable;—seeing these things, if any question remains as to whether the test of inconceivability should in this case be regarded as having any degree of validity at all, there can, I think, be no reasonable doubt that such degree should be regarded as of the smallest.

§ 17. Let us then turn to the other considerations which have been supposed to justify the assertion that nothing can have caused our mind save another Mind. Neglecting the crushing fact that "it does not account for Mind to refer it to another Mind for its origin," let as see what positive reasons there are for concluding that no other influence than Intelligence can possibly have produced our intelligence.

§ 18. First we may notice the argument which is well and tersely presented by Locke, thus:—"Whatsoever is first of all things must necessarily contain in it, and actually have, at least, all the perfections that can ever after exist; nor can it ever give to another any perfection that it hath not actually in itself, or at least in a higher degree; it necessarily follows that the first eternal being cannot be Matter." Now, as this presentation is strictly formal, I shall first meet it with a formal reply, and this reply consists in a direct contradiction. It is simply untrue that "whatsoever is first of all things must necessarily contain in it, and actually have, at least, all the perfections that can after exist;" or that it can never "give to another any perfection that it hath not actually in itself." In a sense, no doubt, a cause contains all that is contained in its effects; the latter content being potentially present in the former. But to say that a cause already contains actually all that its effects may afterwards so contain, is a statement which logic and common sense alike condemn as absurd.

Nevertheless, although the argument now before us thus admits of a childishly easy refutation on strictly formal grounds, I suspect that in substance the argument in a general way is often relied upon as one of very considerable weight. Even though it is clearly illogical to say that causes cannot give to their effects any perfection which they themselves do not