experience whatsoever must tap the realm of essence, and throw the
light of attention on one of its constituent forms. This is, if you
will, a trivial achievement; what would be really a surprising feat,
and hardly to be credited, would be that the human mind should grasp
the _constitution of nature_; that is, should discover which is the
particular essence, or the particular system of essences, which actual
existence illustrates. In the matter of physics, truly, we are reduced
to skimming the surface, since we have to start from our casual
experiences, which form the most superficial stratum of nature, and
the most unstable. Yet these casual experiences, while they leave us
so much in the dark as to their natural basis and environment,
necessarily reveal each its ideal object, its specific essence; and we
need only arrest our attention upon it, and define it to ourselves,
for an eternal possibility, and some of its intrinsic characters, to
have been revealed to our thought.

Whatever, then, a man's mental and moral habit might be, it would
perforce have affinity to some essence or other; his life would
revolve about some congenial ideal object; he would find some sorts of
form, some types of relation, more visible, beautiful, and satisfying
than others. Mr. Russell happens to have a mathematical genius, and to
find comfort in laying up his treasures in the mathematical heaven. It
would be highly desirable that this temperament should be more common;
but even if it were universal it would not reduce mathematical essence
to a product of human attention, nor raise the "beauty" of mathematics
to part of its essence. I do not mean to suggest that Mr. Russell
attempts to do the latter; he speaks explicitly of the _value_ of
mathematical study, a point in ethics and not directly in logic; yet
his moral philosophy is itself so much assimilated to logic that the
distinction between the two becomes somewhat dubious; and as Mr.