determined by, changes going on in the external world; just as it is but a matter of phraseology whether we speak of temperature determining, or being determined by, molecular vibration. All the requirements alike of the free-will and of the bond-will hypotheses are thus satisfied by a synthesis which comprises them both. On the one hand, it would be as impossible for an _un_conscious automaton to do the work or to perform the adjustments of a conscious agent, as it would be for an Edison lamp to give out light and cause a photograph when not heated by an electric current. On the other hand, it would be as impossible for the will to originate bodily motion without the occurrence of a strictly physical process of cerebration, as it would be for light to shine in an Edison lamp which had been deprived of its carbon-burner. The great advantage of this theory is, that it supposes only one stream of causation, in which both mind and motion are simultaneously concerned. The theory, therefore, escapes all the difficulties and contradictions with which both spiritualism and materialism are beset. Thus, motion is supposed to be producing nothing but motion; mind-changes nothing but mind-changes--both producing both simultaneously: neither could be what it is without the other, because without the other neither could be the cause which in fact it is. Impossible, therefore, is the supposition of the materialist that consciousness is adventitious, or that in the absence of mind the changes of the brain could be what they are; for it belongs to the very causation of these movements that they should have a mental side. And equally impossible is the supposition of the spiritualist that the cerebral processes are adventitious, or that in the absence of brain the changes of the mind could be what they are; for it belongs to the very causation of these changes that they should have a material side. Furthermore, the use of mind to animals and to men is thus rendered apparent; for intelligent volition is thus shown to be a true cause of adjustive movement, in that the cerebration which it involves could not otherwise be possible: the causation would not otherwise be complete. FOOTNOTES: [Footnote 8: _Lectures and Essays_, vol. ii. pp. 56-7.] CHAPTER IV. THE WORLD AS AN EJECT.