THE CONCEPT OF NATURE 133 



MENTAL PROCEDURE AND THE CONCEPT OF NATURE 

 (Joshua C. Gregory, B.Sc.) 



It may be misleading to say, with Sir Martin Conway, that " Any fact may 

 be chosen as the centre of all knowledge," and suggestive of error to add, 

 with him, " Any study, if pursued to the end, leads on to all other studies." i 

 The biologist wanders naturally into psychology, because animals seem to 

 be conscious, and the psychologist can hardly avoid metaphysics : such 

 sequences of studies are obvious and inevitable. Geographical analogy, 

 however, may induce error if we think that knowledge is like a territory 

 which can be traversed, with finally similar results, from any starting-point. 

 A traveller will visit the same places and see the same scenes whether he 

 begins his circuit of the globe at Shanghai or New York. In a survey of 

 the earth, or of a territory, the particular physical point of departure is, in 

 essence, indifferent. It partly decides the order of visitation ; but, in 

 principle, a geographical survey, when made, is the same whatever its 

 starting-point. Mental points of departure may be less, perhaps much less, 

 indifferent. Unlike geographical territory, which presents the same features 

 to travellers from all starting-points, knowledge may vary, and vary all 

 through, with the mental beginning of the knower. 



Common sense will probably accept this suggestion. Geographical points 

 of departure seem to be simply entries into established routes ; mental routes 

 seem to be determined, at any rate in part, by their beginnings. Psychology 

 is usually one thing to a former biologist and another thing to a devotee with 

 mystical experiences. Physicists incline to different views of atomic structure 

 from chemists. Different social environments, different educations, and 

 different mental types produce different versions or views within the same 

 field of knowledge. Knowledge seems to be very relative to the point of 

 departure of the knower : his original conceptual outfit seems largely to 

 decide what he will subsequently believe and think. 



Two little girls gave their father, who was a vicar, a birthday present 

 of a Bible. They knew that many people gave books to their father, and 

 wrote in them " with the author's compliments," so they put the same 

 inscription in their gift. In this story. Punch genially indicates a mental 

 habit which Descartes described more sedately : " Whenever men notice 

 some similarity between two things, they are wont to ascribe to each, even 

 in those respects in which the two differ, what they have found to be true 

 of the other." 2 The little maids assumed that a method appropriate to 

 one situation would be equally appropriate to another ; their elders make less 

 obvious mistakes, but they have the same habit. Descartes perceived the 

 analogical method that largely dominates the human mind. When Hobbes 

 remarked, "... men measure, not only other men, but all other things, 

 by themselves," ^ he singled out from this analogical method of working 

 its aspect of working on mental models. Animism uses the conscious being 

 as its mental model, and compares everything else with it. Our most familiar 

 experiences, our most deeply or clearly realised conceptions, our habitual 

 methods of explanation, serve as mental models when we are faced with 

 new facts or situations and invited to interpret them. Knowledge can, of 

 course, prosper by analogies. But it seems clear that mental routes must 

 be greatly influenced by their points of departure, for these points of departure 

 are, in part at any rate, the mental models with which the mind starts. 

 The movements of thought demonstrate changes in the general stock of 

 mental models from age to age : it is possible that the human mind's original 



^ The Domain of Art. 



2 Rules for the Direction of our Intelligence, trans, by Haldane and Ross, 

 Rule I. 



^ Leviathan, ch. ii. 



