SCIENTIFIC STUDY OF HUMAN TESTIMONY. 59 



science and specialism are identical ; not to specialize is to lose the prizes 

 of life. Germany, which in philosophy and science does the original 

 thinking of the world, is, as we all know, a nation of specialists. 



There are, it is true, degrees of specialism, and the term is largely a 

 relative one : in medicine, where the word is mostly used, and where 

 until recently it has been a term of more or less reproach, all general 

 practitioners are really specialists, since medicine and surgery are both 

 offshoots from the professions of the priest and the barber ; in biology, 

 some are authorities only on paleontology, others on natural history in 

 general, others on some special branch, as entomology, others still on 

 some one insect, as the bee; and this subdivision is continually going on 

 with the evolution of systematized knowledge. These statements may 

 be truisms to students of sociology, but they are truisms that are for- 

 gotten by all the writers on testimony, although, as we shall see, they 

 lie at the root of the reconstruction of the principles of evidence. 



Equally important in its bearings on the scientific study of testimony 

 is the recognition of the fact that memory is far more untrustworthy 

 than has been commonly supposed. But a very small fraction of the 

 impressions made on the cerebrum are so far retained as ever to be called 

 up at will. Theoretically, the brain is like a target on which every idea 

 that is evolved makes a permanent impression which no subsequent im- 

 pressions can thoroughly destroy ; practically, it is rather like a series 

 of sieves by which thoughts are sifted through various stages below and 

 on the borders of consciousness and recollection, while only the coarser 

 and larger grains are retained where they can be used when needed. 

 Under the stress of special excitements as in the terror of drowning or 

 protracted falling, or in trance, impressions long forgotten are revived 

 and rise to temporary consciousness, so that men suppose that the pano- 

 rama of all their past lives is passing before them ; but, even under such 

 exceptional crises, it is certain that only a comparatively few of our 

 mental impressions actually reappear ; some long-forgotten events arise 

 with vivid distinctness, and the startled subject believes that all his life 

 is let loose. 



Nearly all the acquisitions and experiences of life are forgotten, 

 even by the best memories ; only the tiniest trifle of past events or past 

 knowledge can ever be recalled. How dreams are forgotten we all 

 know, but the difference between the recollection of sleeping and wak- 

 ing thoughts is only one of degree ; by the standard of memory, all life 

 is a dream. The pleasant experiences of infancy and early childhood, 

 which, if they could be recalled at will, would so enrich and glorify hu- 

 man existence, are to us as though they had never been ; as maturity 

 appears, childhood dies. 



Children really, as compared with adults, have very poor memories ; 

 they forget almost everything ; even in infancy the experiences of each 

 year are wiped out by the experiences of the succeeding year ; bright 



