September 22, 1916] 



SCIENCE 



411 



But, for the purposes of science, what is 

 the actual world? Has science to wait for 

 the termination of the metaphysical debate 

 till it can determine its own subject-matter? 

 I suggest that science has a much more 

 homely starting-ground. Its task is the 

 discovery of the relations which exist within 

 that flux of perceptions, sensations and 

 emotions which forms our experience of 

 life. The panorama yielded by sight, 

 sound, taste, smell, touch and by more in- 

 choate sensible feelings, is the sole field of 

 its activity. It is in this way that science 

 is the thought organization of experience. 

 The most obvious aspect of this field of 

 actual experience is its disorderly char- 

 acter. It is for each person a continuum, 

 fragmentary, and with elements not clearly 

 differentiated. The comparison of the sen- 

 sible experiences of diverse people brings 

 its own difficulties. I insist on the radically 

 untidy, ill-adjusted character of the fields 

 of actual experience from which science 

 starts. To grasp this fundamental truth is 

 the first step in wisdom, when constructing 

 a philosophy of science. This fact is con- 

 cealed by the influence of language, 

 moulded by science, which foists on us ex- 

 act concepts as though they represented 

 the immediate deliverances of experience. 

 The result is that we imagine that we have 

 immediate experience of a world of per- 

 fectly defined objects implicated in per- 

 fectly defined events which, as known to us 

 by the direct deliverance of our senses, 

 happen at exact instants of time, in a 

 space formed by exact points, without parts 

 and without magnitude: the neat, trim, 

 tidy, exact world which is the goal of scien- 

 tific thought. 



My contention is that this world is a 

 world of ideas, and that its internal rela- 

 tions are relations between abstract con- 

 cepts, and that the elucidation of the pre- 

 cise connection between this world and the 



feelings of actual experience is the funda- 

 mental question of scientific philosophy. 

 The question which I am inviting you to 

 consider is this: How does exact thought 

 a Pply to the fragmentary, vague continue/, 

 of experience? I am not saying that it 

 does not apply, quite the contrary. But I 

 want to know how it applies. The solu- 

 tion I am asking for is not a phrase, how- 

 ever brilliant, but a solid branch of sci- 

 ence, constructed with slow patience, show- 

 ing in detail how the correspondence is 

 effected. 



The first great steps in the organization 

 of thought were due exclusively to the prac- 

 tical source of scientific activity, without 

 any admixture of theoretical impulse. 

 Their slow accomplishment was the cause 

 and also the effect of the gradual evolu- 

 tion of moderately rational beings. I mean 

 the formation of the concepts of definite 

 material objects, of the determinate lapse 

 of time, of simultaneity, of recurrence, of 

 definite relative position, and of analogous 

 fundamental ideas, according to which the 

 flux of our experiences is mentally arranged 

 for handy reference: in fact, the whole 

 apparatus of common-sense thought. Con- 

 sider in your mind some definite chair. 

 The concept of that chair is simply the con- 

 cept of all the interrelated experiences con- 

 nected with that chair — namely, of the ex- 

 periences of the folk who made it, of the 

 folk who sold it, of the folk who have seen 

 it, or used it, of the man who is now experi- 

 encing a comfortable sense of support, com- 

 bined with our expectations of an analogous 

 future, terminated finally by a different set 

 of experiences when the chair collapses and 

 becomes fire-wood. The formation of that 

 type of concept was a tremendous job, and 

 zoologists and geologists tell us that it took 

 many tens of millions of years. I can well 

 believe it. 



I now emphasize two points. In the first 



