Note 165 — Chapter VI · THE LOGICAL CHARACTER OF DESCRIPTIVE SCIENCE

To put the matter more succinctly, as regards the position of Chemistry and Biology, we may say that while chemical and biological facts are never merely mechanical, chemical and biological science, so far as they subserve the strictly scientific interest of calculation and the formulation of general rules, must always be so. The facts only lend themselves to this special purpose in so far as they admit of being, without sensible error, treated as if they conformed to the postulates of universal Mechanism. The special and more difficult case of psychological facts I reserve for separate discussion in the following Book (infra, Bk. IV. chap. 1).

I am glad to be able to refer the reader, for a view of the logical worth of the mechanical postulates which appears in principle identical with my own, to the interesting discussion of Mr. W. R. B. Gibson in Personal Idealism, p. 144 ff.