es to
distinguish them from the group of sciences I have been discussing at
length. What marks them out is, that the facts with which the
investigator has to deal are known by him with sufficient clearness to
leave him usually in little doubt as to the use which he can make of
them. His knowledge is clear enough for the purpose in hand, and his
work is justified by its results. What is the relation of such
sciences as these to philosophy?

79. THE STUDY OF SCIENTIFIC PRINCIPLES AND METHODS.--It is one thing to
have the instinct of the investigator and to be able to feel one's way
along the road that leads to new knowledge of a given kind, and it is
another thing to have the reflective turn of mind that makes one
clearly conscious of just what one has been doing and how one has been
doing it. Men reasoned before there was a science of logic, and the
sciences made their appearance before what may be called the logic of
the sciences had its birth.

"It may be truly asserted," writes Professor Jevons,[1] "that the rapid
progress of the physical sciences during the last three centuries has
not been accompanied by a corresponding advance in the theory of
reasoning. Physicists speak familiarly of Scientific Method, but they
could not readily describe what they mean by that expression.
Profoundly engaged in the study of particular classes of natural
phenomena, they are usually too much engrossed in the immense and ever
accumulating details of their special sciences to generalize upon the
methods of reasoning which they unconsciously employ. Yet few will
deny that these methods of reasoning ought to be studied, especially by
those who endeavor to introduce scientific order into less successful
and methodical branches of knowledge."

Professor Jevons suggests that it is lack of time and attention that
prevents the scientific investigator from attaining to a clear
conception of what is meant by scientific method. This has something
to do with it, but I think we may also maintain that the work of the
investigator and that of the critic are somewhat different in kind, and
require somewhat different powers of mind. We find a parallel to this
elsewhere. Both in literature and in art men may be in the best sense
productive, and yet may be poor critics. We are often wofully
disappointed when we attend a lecture on poetry by a poet, or one on
painting by an artist.

It may be said: If what is maintained above regarding the