possibly be made to connote anything except what the speaker means. It
adheres to the subject matter of discourse with a tenacity which no
criticism can overcome. In consequence, whenever a science is reduced
to a mathematical form its conclusions are no longer the subject of
philosophical attack. To secure the same desirable quality in all other
scientific language it is necessary to give it, so far as possible, the
same simplicity of signification which attaches to mathematical
symbols. This is not easy, because we are obliged to use words of
ordinary language, and it is impossible to divest them of whatever they
may connote to ordinary hearers.

I have thus sought to make it clear that the language of science
corresponds to that of ordinary life, and especially of business life,
in confining its meaning to phenomena. An analogous statement may be
made of the method and objects of scientific investigation. I think
Professor Clifford was very happy in defining science as organized
common-sense. The foundation of its widest general creations is laid,
not in any artificial theories, but in the natural beliefs and
tendencies of the human mind. Its position against those who deny these
generalizations is quite analogous to that taken by the Scottish school
of philosophy against the scepticism of Hume.

It may be asked, if the methods and language of science correspond to
those of practical life, why is not the every-day discipline of that
life as good as the discipline of science? The answer is, that the
power of transferring the modes of thought of common life to subjects
of a higher order of generality is a rare faculty which can be acquired
only by scientific discipline. What we want is that in public affairs
men shall reason about questions of finance, trade, national wealth,
legislation, and administration, with the same consciousness of the
practical side that they reason about their own interests. When this
habit is once acquired and appreciated, the scientific method will
naturally be applied to the study of questions of social policy. When a
scientific interest is taken in such questions, their boundaries will
be extended beyond the utilities immediately involved, and one
important condition of unceasing progress will be complied with.

XXI

THE OUTLOOK FOR THE FLYING-MACHINE

Mr. Secretary Langley's trial of his flying-machine, which seems to
have come to an abortive issue for the time, strikes a sym