Page:Mind (New Series) Volume 9.djvu/306

 292 G. E. MOOEE : would be a bold assertion that no one ever had believed or would believe with ease that two and two make five. And it the statement be general only and not universal, it would apply to many more truths than are commonly thought to be necessary, as, for instance, to the existence of the sun and of the earth. It can scarcely be maintained that such facts have failed to be called necessary, solely because it was not perceived that their opposites were hard to believe. The most plausible way, then, in which it might be attempted to show that the meaning of necessity always involved a refer- ence to the feeling of compulsion, fails at least to cover the distinction between necessary and existential truths. The most plausible expression of this theory would take the form : That is always necessary, belief in which would generally excite a feeling of compulsion, if we tried to believe its opposite. And this definition of necessity, while it is doubt- ful even whether it would apply to most cases of supposed necessary truths, certainly fails in that it will apply to many others as well. It seems questionable how far this feeling of compulsion is to be identified with the impression from which Hume sought to derive the idea of necessity. But his account of how we come to think events necessarily connected certainly implies quite a different meaning of necessity, which must be care- fully distinguished from this. What he says is that when a succession of two events has been repeated often enough, the mind has a habit of reproducing the idea of the second on the occurrence of the impression of the first. He does not seem to maintain that it feels compelled to have the idea of the second event. But unless he does mean this, where is the impression of necessity for which he was seeking ? Either he must mean that there are constant successions among mental events just as there are among physical ; but in that case it would seem that the succession in the mind can give rise to no idea different from that to which the physical succession might of itself give rise. Necessity in this case means merely constant succession, and Hume's reference to the habits of the mind is quite superfluous. Or else he means that the mental habit does actually compel us to think of the second event on occurrence of the first. But in this case he is illegitimately transferring to the contents of the mind that very idea of necessary connexion which he is seeking to deny to physical events. For, on his own showing, we have no title to say anything more of mental contents than that they do succeed one another in certain fixed sequences. His question is : What is the meaning of