The word identity, as Dr. Bain allows,15 is applied loosely in various senses. We speak of the identity of the English people since the Norman Conquest, and of the identity of a regiment, a bank, or a newspaper during a long period, though not a single constituent of the object persists unchanged. But in none of these cases have we anything approaching to what we call personal identity. There is an apparent external unity which binds under a common notion really different sets of things or events. The aggregate of elements composing the object at one time, may be in every particular different from what they were at another. There is no real identity in such a case, and rational memory or self-consciousness would be impossible to a being constituted solely of such changing materials.

As regards the mark on the tree, abstracting from the Peripatetic doctrine of a single vital principle persisting throughout the life history of every organism

-a question beside the present discussion-we may assert that the only sameness which connects the incision of my name on the young sapling with that found on the tree of thirty years later, lies in the extrinsic circumstance that similar thoughts will be produced in minds which contemplate the impressions at the different periods. Identity in the physical impressions themselves there is none. The imprinted name originally consisted merely of certain vacant spaces at a certain height from the ground, and surrounded by portions of timber. But the exact place where the former empty interstices were situated is now occupied by the wood of the tree, while six inches higher, and spread out over a much larger space, and surrounded by new timber, is what we call the old impression, because it arouses in the mind a representation of the same object as formerly. The identity of a scar on the human body is of a like character. Now, modifications in the cellular substance of the brain produced on the occasion of sensations, were they similarly preserved, would retain no more real unity with the original impression than is found in the case of the 15 Moral Science, Appendix, p. 96.

EE

poplar tree. To argue that the present modification o the brain may be the groundwork of a disposition to vibrate in a manner similar to that occasioned by the original impression, and so may evoke a similar mental state, is to miss the precise point to be explained. The occurrence of a new vibration or mental state like to the original cannot be said to constitute a remembrance of the former, any more than to-day can be said to remember this day last week or last year. There is required, in addition to the detached events, a persisting indivisible being which connects them.16

There are certain other scholastic difficulties against the simplicity and spirituality of the soul, which possessed some weight and popularity during the middle ages, but for which we can afford only brief space here. Among the chief of this class are the following: (a) The soul cannot be simple and indivisible, because it is present throughout an extended body. (b) The soul moves the body, but such a result can only be effected by contact, which would be impossible if the soul did not touch the body. This, however, implies that the soul itself must be extended. (c) A simple spiritual soul is inconceivable. (d) The soul is the substantial form of a material body, and a form is of necessity absolutely dependent on its material subject. Therefore the soul is not spiritual.

We may reply in scholastic style: (a) A simple, indivisible force, substance, or energy cannot be quantitatively present—that is, having parts alongside of parts— throughout an extended subject: Allowed. It cannot be essentially present, that is, by exercise of its virtue or influence ubiquitously in such a subject: Denied. Natural Theology proves that God is thus essentially present, exercising His power everywhere in the universe, yet

16 "I may be tossed about between the most contrary ideas, the most opposite sentiments, without ceasing to be myself; and, on the contrary, two men thinking the same thing, as, for instance, the series of numbers, will not become for that reason one and the same man; several chords producing the same note are not the same chord. Thus, the consciousness of personal identity is not explained by the identity of vibrations any more than by the persistence of form." (Janet, op. cit. pp. 141, 142.)

not in an extended manner. (b) We simply deny that motion can be produced in a body only by physical contact of one extended surface upon another, or that a simple force or energy cannot affect the condition of matter. (c) If inconceivable means incapable of being pictured by the imagination: Allowed; but then many things unimaginable in this sense are held to exist. If inconceivable means self-contradictory or positively unthinkable: Denied. (d) Although the human soul is, in the Scholastic theory, the form of the body, yet as St. Thomas says, it is not completely immersed in its material subject; that is, in certain of its functions, such as intellectual cognition and volition, the soul exceeds the range of activity possible to a merely corporeal form.

Readings. On the subject-matter of the two last chapters, cf. St. Thomas, Sum. i. q. 75. ` On the Substantiality of the Soul, cf. John Rickaby, Metaphysics, pp. 245-260; Balmez, op. cit. Bk. IX. cc. 6-9 and 11, 12; Margerie, op. cit. pp. 128-191; Janet, Materialism of the Present Day, c. vii.; Ladd, Physiological Psychology, Pt. III. cc. i. and iv.; Kleutgen, op. cit. §§ 791-807.

CHAPTER XXII.

RECENT THEORIES CONCERNING THE SOUL: THE "DOUBLE-ASPECT."

DOCTRINE OF THE

THE value of a theory is never fully apprehended until it is compared with the most plausible counterhypothesis. Accordingly, the force of the arguments by which the reality of an indivisible spiritual soul is proved cannot be fairly estimated until we have taken a rapid view of the rival doctrine put forward by the ablest opponents at the present day.

THE DOCTRINE OF THE DOUBLE-ASPECT.-The new faith has been aptly styled the Double-Aspect Theory. Marked by rather important differences in the hands of its various exponents, this view in all its forms adheres to one cardinal tenet-that Mind and Body are not two distinct realities, but merely two "aspects," "sides," or "phases" of one and the same thing. The late Professor Clifford, Dr. Bain, Mr. Spencer, G. H. Lewes, and Professor Huxley are amongst the best known advocates of this doctrine here at home, and we will seek to briefly explain and examine their views.

Professor Clifford, with characteristic hardihood, invented the term mind-stuff, to denote the material

out of which he asserts that human minds are formed. According to him there is attached to every particle of matter in the universe a bit of rudimentary feeling or intelligence. intelligence. When the molecules of matter come together in certain forms and proportions, the attached atoms of mental life. fuse into a complete self-conscious mind.1 Neither the molecules of matter, however, nor the appended morsels of mind can have any influence on the other. At least, this is Clifford's doctrine at times: "The physical facts go along by themselves, and the mental facts go along by themselves. There is a parallelism between them, but there is no interference of one with the other.'

"2

The only arguments suggested in defence of these doctrines are the assertions: (1) that Physiology has established an absolute and complete parallelism between psychical and physical facts; (2) that physics has proved the impossibility of any mutual interaction between them; and (3) lastly, the fact that Clifford's theory is essential to the supposed truth, now taken as demonstrated, nay, almost as axiomatic, that all of us, both mind and body, have been developed out of inferior

"When molecules are so combined as to form the film on the under-side of a jelly-fish, the elements of mind-stuff which go along with them are so combined as to form the faint beginnings of sentience. When the molecules are so combined as to form the brain and nervous system of a vertebrate, the corresponding elements of mind-stuff are so combined as to form some kind of consciousness. When matter takes the complex form of the living human brain, the corresponding mind-stuff takes the form of human consciousness having intelligence and volition." ("On the Nature of Things in Themselves," Mind, Vol. III. pp. 64, 65.)

2 Fortnightly Review, Dec. 1874, P. 728.