JAMES WARD, Naturalism and Agnosticism. 255 that it leads us to assume "unconscious mental states" as the correlates of certain nervous processes. Yet, provided that the fictions answer their purpose, which is to facilitate the description of the various nervous and mental processes taking place in the sentient organism, their usefulness would seern to justify our em- ployment of them. I do not for a moment imagine that Dr. Ward would deny this ; only it could have been wished, for the sake of his readers, that he had made it clearer that it is " Parallelism " as a metaphysical doctrine, not "Parallelism" as a convenient working hypothesis within a certain restricted sphere, which sound philosophy has to reject. There is another, and a more important, question of philosophical first principles, which is suggested by this section of the Gifford Lectures. With the rejection of the metaphysical doctrine of "Parallelism" disappears the whole argument for the strictly mechanical determination of the course of the universe. If mind can be thought of as an originator of changes in the physical order there is at once an end of all possi- bility of calculating the course of the world from purely kinetical data ; we are finally delivered from that " mechanical prediction " of human action in which certain among us still believe, and of which Prof. Ward truly says that it would be "incompatible with freedom ". But does determinism as a philosophical theory stand , or fall with determination by purely mechanical antecedents? From what Prof. Ward says at page 281 of volume ii. on the relation of freedom and contingency, it appears that he would answer this question in the affirmative. Is it not however con- , ceivable that both idealism and determinism may be the truth ? In that case the course of the world would be strictly determined, only the "determinants," so to speak, would not be masses and accelerations ; prediction would be possible, but not mechanical prediction. Some such view seems to have been actually enter- tained by Plato, who held with Prof. Ward that mind is the source of movement, and at the same time that the behaviour of my , mind or yours is determined by heredity and social environment. Such a view, again, would give us all the freedom that we seem to care about ; prediction of our conduct, as such, appears indeed to cause neither annoyance nor alarm, unless it is avowedly based upon data from which the psychical quality of our own and our ancestors' selves has been excluded, i.e. unless it is " mechanical prediction". It would be interesting to have Prof. Ward's opinion of Spinoza's definition of the human mind as aeternus cogitandi modus qui ab alio aeterno cogitandi modo determinatur et hie iterum ab alio, et sic in infinitum. In the examination and refutation of dualism which follows on the rejection of the doctrine of " Parallelism " Prof. Ward is quite at his best, and it is a question whether this particular section is not the most thoroughly original part of the whole book. To the present writer at least the demonstration that immediate experience knows nothing of the dualism of " subjective states "