NECESSARY TRUTHS— EFFECTS OF EXPERIENCE. 621 



corollary that an infinity of experiences will produce a psychical relation 

 that is indissoluble. Though such infinity of experiences cannot be 

 received by a single individual, yet it may be received by the succession 

 of individuals forming a race. And if there is a transmission of induced 

 tendencies in the nervous system, it is inferrible that all psychical rela- 

 tions whatever, from the necessary to the fortuitous, result from the 

 experiences of the corresponding external relations ; and are so brought 

 into harmony with them. 



"Thus, the experience-hypothesis furnishes an adequate solution. 

 The genesis of instinct, the development of memory and reason out of 

 it, and the consolidation of rational actions and inferences into in- 

 stinctive ones, are alike explicable on the single principle that the 

 cohesion between psychical states is proportionate to the frequency with 

 which the relation between the answering external phenomena has been 

 repeated in experience. 



" The universal law that, other things equal, the cohesion of psy- 

 chical states is proportionate to the frequency with which they have 

 followed one another in experience, supplies an explanation of the so- 

 called ' forms of thought,' as soon as it is supplemented by the law that 

 habitual psychical successions entail some hereditary tendency to such 

 successions, which, under persistent conditions, will become cumulative 

 in generation after generation. We saw that the establishment of those 

 compound reflex actions called instincts is comprehensible on the prin- 

 ciple that inner relations are, hy perpetual repetition, organized into 

 correspondence with outer relations. We have now to observe that the 

 establishment of those consolidated, those indissoluble, those instinctive 

 mental relations constituting our ideas of Space and Time is compre- 

 hensible on the same principle. For if even to external relations- 

 that are often experienced during the life of a single organism, answer- 

 ing internal relations are established that become next to automatic — 

 if such a combination of psychical changes as that which guides a savage 

 in hitting a bird with an arrow becomes, by constant repetition, so or- 

 ganized as to be performed almost without thought of the processes of 

 adjustment gone through — and if skill of this kind is so far transmissible 

 that particular races of men become characterized by particular apti- 

 tudes, which are nothing else than partially-organized psychical connec- 

 tions ; then, if there exist certain external relations which are 

 experienced by all organisms at all instants of their waking lives — 

 relations which are absolutely constant, absolutely universal — there will 

 be established answering internal relations that are absolutely constant, 

 absolutely universal. Such relations we have in those of Space and 

 Time. The organization of subjective relations adjusted to these objec- 

 tive relations has been cumulative, not in each race of creatures only,, 

 but throughout successive races of creatures ; and such subjective rela- 

 tions have, therefore, become more consolidated than all others. Being 

 experienced in every perception and every action of each creature, these 

 connections among outer existences must, for this reason too, be 



