Altogether, the Soul is an outbirth of that sort of philosophizing whose great maxim, according to Dr. Hodgson, is: "Whatever you are totally ignorant of, assert to be the explanation of everything else."
Locke and Kant, whilst still believing in the soul, began the work of undermining the notion that we know anything about it. Most modern writers of the mitigated spiritualistic, or dualistic philosophy—the Scotch school, as it is often called among us—are forward to proclaim this ignorance, and to attend exclusively to the verifiable phenomena of self-consciousness, as we have laid them down. Dr. Wayland, for example, begins his Elements of Intellectual Philosophy with the phrase "Of the essence of Mind we know nothing," and goes on: "All that we are able to affirm of it is that it is something which perceives, reflects, remembers, imagines, and wills; but what that something is which exerts these energies we know not. It is only as we are conscious of the action of these energies that we are conscious of the existence of mind. It is only by the exertion of its own powers that the mind becomes cognizant of their existence. The cognizance of its powers, however, gives us no knowledge of that essence of which they are predicated. In these respects our knowledge of mind is precisely analogous to our knowledge of matter." This analogy of our two ignorances is a favorite remark in the Scotch school. It is but a step to lump them together into a single ignorance, that of the 'Unknowable' to which any one fond of superfluities in philosophy may accord the hospitality of his belief, if it so please him, but which any one else may as freely ignore and reject.
The Soul-theory is, then, a complete superfluity, so far as accounting for the actually verified facts of conscious experience goes. So far, no one can be compelled to subscribe to it for definite scientific reasons. The case would rest here, and the reader be left free to make his choice, were it not for other demands of a more practical kind.
The first of these is Immortality, for which the simplicity and substantiality of the Soul seem to offer a solid guarantee. A 'stream' of thought, for aught that we see to be contained in its essence, may come to a full stop at any moment; but a simple substance is incorruptible, and will, by its own inertia, persist in Being so long as the Creator does not by a direct miracle snuff it out. Unquestionably this is the stronghold of the spiritualistic belief,—as indeed the popular touchstone for all philosophies is the question, "What is their bearing on a future life?"
The Soul, however, when closely scrutinized, guarantees no immortality of a sort we care for. The enjoyment of the atom-like simplicity of their substance in sæcula sæculorum would not to most people seem a consummation devoutly to be wished. The substance must give rise to a stream of consciousness continuous with the present stream, in order to arouse our hope, but of this the mere persistence of the substance per se offers no guarantee. Moreover, in the general advance of our moral ideas, there has come to be something ridiculous in the way our forefathers had of grounding their hopes of immortality on the simplicity of their substance. The demand for immortality is nowadays essentially teleological. We believe ourselves immortal because we believe ourselves fit for immortality. A 'substance' ought surely to perish, we think, if not worthy to survive; and an insubstantial 'stream' to prolong itself, provided it be worthy, if the nature of Things is organized in the rational way in which we trust it is. Substance or no substance, soul or 'stream,' what Lotze says of immortality is about all that human wisdom can say:
"We have no other principle for deciding it than this general idealistic belief: that every created thing will continue whose continuance belongs to the meaning of the world, and so long as it does so belong; whilst every one will pass away whose reality is justified only in a transitory phase of the world's course. That this principle admits of no further application in human hands need hardly be said. We surely know not the merits which may give to one being a claim on eternity, nor the defects which would cut others off."[275]
A second alleged necessity for a soul-substance is our forensic responsibility before God. Locke caused an uproar when he said that the unity of consciousness made a man the same person, whether supported by the same substance or no, and that God would not, in the great day, make a person answer for what he remembered nothing of. It was supposed scandalous that our forgetfulness might thus deprive God of the chance of certain retributions, which otherwise would have enhanced his 'glory.' This is certainly a good speculative ground for retaining the Soul—at least for those who demand a plenitude of retribution. The mere stream of consciousness, with its lapses of memory, cannot possibly be as 'responsible' as a soul which is at the judgment day all that it ever was. To modern readers, however, who are less insatiate for retribution than their grandfathers, this argument will hardly be as convincing as it seems once to have been.
One great use of the Soul has always been to account for, and at the same time to guarantee, the closed individuality of each personal consciousness. The thoughts of one soul must unite into one self, it was supposed, and must be eternally insulated from those of every other soul. But we have already begun to see that, although unity is the rule of each man's consciousness, yet in some individuals, at least, thoughts may split away from the others and form separate selves. As for insulation, it would be rash, in view of the phenomena of thought-transference, mesmeric influence and spirit-control, which are being alleged nowadays on better authority than ever before, to be too sure about that point either. The definitively closed nature of our personal consciousness is probably an average statistical resultant of many conditions, but not an elementary force or fact; so that, if one wishes to preserve the Soul, the less he draws his arguments from that quarter the better. So long as our self, on the whole, makes itself good and practically maintains itself as a closed individual, why, as Lotze says, is not that enough? And why is the being-an-individual in some inaccessible metaphysical way so much prouder an achievement?[276]