200 PSYCHOLOGY. 



fered a breucli. The two ends joiu each other smoothly 

 over the gaj) ; and only the sight of our wound assures us 

 that we must have been living through a time which for 

 our immediate consciousness was non-existent. Even in 

 sleep tliis sometimes happens : We think Ave liave had no 

 nap, and it takes the clock to assure us that we are wrong.* 

 We thus may live through a real outward time, a time 

 known by the psychologist who studies us, and yet not 

 feel the time, or infer it from any inward sign. The ques- 

 tion is, how often does this happen ? Is consciousness 

 really discontinuous, incessantly interrupted and recom- 

 mencing (from the psychologist's point of view) ? and does 

 it only seem continuous to itself by an illusion analogous 

 to that of the zoetrope ? Or is it at most times as continu- 

 ous outwardly as it inwardly seems ? 



It must be confessed that we can give no rigorous 

 answer to this question. Cartesians, who hold that the 

 essence of the soul is to think, can of course solve it 

 a priori, and explain the appearance of thoughtless inter- 

 vals either by lapses in our ordinary memory, or by the 

 sinking of consciousness to a minimal state, in which per- 

 haps all that it feels is a bare existence which leaves no 

 particulars behind to be recalled. If, however, one have 

 no doctrine about the soul or its essence, one is free to take 

 the appearances for what they seem to be, and to admit 

 that the mind, as well as the body, may go to sleep. 



Locke was the first prominent champion of this latter 

 view, and the pages in which he attacks the Cartesian belief 

 are as spirited as any in his Essay. " Every drowsy nod 

 shakes their doctrine who teach that their soul is always 

 thinking." He will not believe that men so easily forget. 

 M. Joutitroy and Sir W. Hamilton, attacking the question in 

 the same empirical way, are led to an opposite conclusion. 

 Their reasons, briefly stated, are these : 



* Messrs. Paytoa Speuce (Journal of Spec. Phil., x. 338, xiv. 286) 

 and M. M. Garver (Amer. Jour, of Science, 3d series, xx. 189) argue, the 

 one from speculative, the other from experimental grounds, that, the physi- 

 cal couiiitiou of consciousness being neural vibration, the consciousness 

 must itself be incessantly iuterrui)ted by unconsciousness— about fifty times 

 a second, according to Garver. 



