This removes the chief, if not the only
ground for the view that all the truths of Science are only 'partial'.
At the same time, the proof that pure mathematics is a strictly logical
development and that all its conclusions are of the hypothetical form,
'if _a b c_ ..., then _x_' definitely disproves the popular Kantian
doctrine that _sense_-data are a necessary constituent of scientific
knowledge. And with this dogma falls the _main_ ground for the denial
that knowledge about the soul and God is attainable. The recovery of a
sounder philosophical method has, as Mr. Russell himself says, disposed
of what was yesterday the accepted view that the function of Philosophy
is to narrow down the range of possible interpretations of facts until
only one is left. Philosophy rather opens doors than shuts them. It
multiplies the number of logically possible sets of premisses from which
consequences agreeing with empirical facts may be inferred. Mr.
Russell's unreasoned anti-theism seems to me to make him curiously blind
to an obvious application of this principle. On the other side, the
revived attention to the logical methods of the sciences is killing the
crude sensationalism of the days which saw the first publication of
Mach's _Science of Mechanics_ and Pearson's _Grammar of Science_. The
claims of 'induction' to be a method of establishing truths may be
fairly said to have been completely exposed. It is clearer now than it
was when Kant made the observation that each of the 'sciences' contains
just so much science as it contains mathematics, and that the Critical
Philosophy was fully justified in insisting that all science implies
universal _a priori_ postulates, though it went wrong in thinking that
these postulates are laws of the working of the human mind or are 'put
into' things by the human mind. How far Science has moved away from
crude sensationalistic empiricism may be estimated by a comparison of
the successive editions of the _Grammar of Science_. It must always have
been apparent to an attentive reader that the chapters of that
fascinating book which deal directly with the leading principles of
Physics and Biology are of very different quality from the earlier
chapters which expound, with many self-contradictions and much wrath
against metaphysicians and theologians whom the writer seems never to
have tried to understand, the fantastic 'metaphysics of the
telephone-exchange'. But the difference of quality is more mar