onstration. It is true the diagram I have
in view includes all these particulars; but then there is not
the least mention made of them in the proof of the
proposition."[140:6]

Of the total conditions present in the concrete picture of a triangle,
one may in one's calculations neglect as many as one sees fit, and work
with the remainder. Then, if one has clearly distinguished the
conditions used, one may confidently assert that whatever has been found
true of them holds regardless of the neglected conditions. These may be
missing or replaced by others, provided the selected or (for any given
investigation) essential conditions are not affected. That which is true
once is true always, provided time is not one of its conditions; that
which is true in one place is true everywhere, provided location is not
one of its conditions. But, given any concrete situation, the more
numerous the conditions one ignores in one's calculations, the less
adequate are one's calculations to that situation. The number of its
inhabitants, and any mathematical operation made with that number, is
true, but only very abstractly true of a nation. A similar though less
radical abstractness appertains to natural science. Simple qualities of
sound or color, and distinctions of beauty or moral worth, together with
many other ingredients of actual experience attributed therein to the
objects of nature, are ignored in the mechanical scheme. There is a
substitution of certain mechanical arrangements in the case of the first
group of properties, the simple qualities of sense, so that they may be
assimilated to the general scheme of events, and their occurrence
predicted. But their intrinsic qualitative character is not reckoned
with, even in psychology, where the physiological method finally
replaces them with brain states. Over and above these neglected
properties of things there remain the purposive activities of thought.
It is equally preposterous to deny them and to describe them in
mechanical terms. It is plain, then, that natural science calculates
upon the basis of only a fraction of the conditions that present
themselves in actual experience. Its conclusions, therefore, though true
so far as they go, and they may be abstractly true of everything, are
completely true of nothing.

[Sidenote: But Scientific Truth is Valid for Reality.]

Sect. 53. Such, in brief, is the general charge of inadequacy which may
be urged against natural