Page:Popular Science Monthly Volume 75.djvu/181

Rh As long as the mind of the interpreter is human, the whole truth of a complex natural object or proposition can never be ascertained from knowledge of its components alone. Or varying this statement, you can never give a full account of any whole in terms of its elements.

In spite of the ocean and the 6tars as illustrating the truth thus formulated, the statement sounds dogmatic. We must examine it farther.

The presumption that biological phenomena may be adequately treated in terms of chemistry and physics takes care of itself so far as strict science is concerned, since its utter futility becomes apparent almost immediately it is put to rigid experimental test. For one thing, it results in constant effort to extend generalizations far beyond where later study will permit them to stand. It leads inevitably to a forcing of evidence, which process sooner or later comes to grief.

One aspect of this forcing is almost certain betrayal into an. illegitimate use of the analogical mode of reasoning. For instance, an analogy is often drawn between the so-called reversed actions in chemistry, and what is spoken of as a return of certain animals—certain worms—to the egg state. As a matter of fact the earlier speaker who drew this analogy might have used the "second-childhood" of the old man as well as the supposed second egg state of the worm. One has as much in common as the other with the chemical process for which correspondence was claimed.

You must not understand by this that I condemn, wholly, comparison and analogy in reasoning. On the contrary, I attach great importance to these, as would become clear were this discussion to be carried into regions where it is not possible for it to go now. In so far as there is resemblance between reversed chemical action and growing old, the fact is illuminating, and to have discovered it is good. My criticism is directed not against pointing out the resemblance, but against not pointing out the difference at the same time, thus leaving the inference that one process accounts for or explains the other. It is in its wider bearings, its bearings beyond strict specialties in science, that the influence of the theory of physical-chemical adequacy in the treatment of life phenomena is most unfortunate. Only when regarded from this larger standpoint does its withering effect on the scientific spirit and method generally, and on man's attitude toward nature, become apparent.

The subject is, according to my view, so vital that I must ask you to look into it more closely. This we can not do without running a little into what these walls are accustomed to hear about under the term theory of knowledge, or epistemology. Most of us would agree that we have to use both our senses and our minds in science. Most would agree too that that workman is the most efficient who uses his instruments the most intelligently—who is not a mere rule-of-thumb