Page:Philosophical Review Volume 2.djvu/203

No. 2.] attention, etc. Its whole importance is centred in the time result, which is statistically treated. Any and every person is accepted as subject; the time curves being plotted with reference at most to differences of age, occupation, and the like, – not with regard to the psychological processes underlying the experimentation. And so with the other subjects common to the anthropometrical and psychological lists. In the paper above quoted Mr. Galton writes: "In testing the delicacy of the senses, I think we should do wrong if we pursued the strict methods appropriate to psycho-physical investigations. We do not want to analyse ... the many elementary perceptions called into action. It is the total result that chiefly interests us. Thus ... [a person] ought to be allowed to handle weights in the way he prefers, and we may disregard the fact that his judgment rests on a blend of many different data, such as pressure, muscular exertion, and appreciation of size."

So far, then, it might seem that the difference between anthropometry and psychology is mainly a difference of end. The experiments are pretty much the same, except that the psychological are more exact; but their results are put to different uses. It should not be difficult to vary them, so as to make these more distinctively anthropometrical, those more distinctively psychological. And all this could have been foreseen, and need not have been specially emphasized here.

Perhaps I can state my argument most emphatically, if I say at once, and in one word, that the difference above and beyond these differences is that of practice. Of course, the widest interpretation must be given to the term. I mean, that an experiment of the type under discussion becomes a psychological experiment, whatever its additional anthropometric value may be, when the subject is a psychologist; whereas the "psychological" experiment, for which the subject has not been psychologically trained, can (with very few exceptions, of which more presently) only have an anthropometric value. To take the first analogy that occurs: suppose that the average