many a mare's nest in its
language, is a safe and obvious enough expression of knowledge. It
involves terms, however, which are in the act of becoming potential.
What is just past, what is just coming, though sensibly continuous with
what is present, are partially infected with nonentity. After a while
human apprehension can reach them only by inference, and to count upon
them is frankly to rely on theory. The other side of the tree, which
common sense affirms to exist unconditionally, will have to be
represented in memory or fancy; and it may never actually be observed by
any mortal. Yet, if I continued my round, I should actually observe it
and know it by experience; and I should find that it had the same status
as the parts now seen, and was continuous with them. My assertion that
it exists, while certainly theoretical and perhaps false, is accordingly
scientific in type. Science, when it has no more scope than this, is
indistinguishable from common sense. The two become distinct only when
the facts inferred cannot be easily verified or have not yet been merged
with the notion representing the given object in most men's minds.

Where science remains consciously theoretical (being as yet contrasted
with ordinary apperception and current thought), it is, ideally
considered, a _pis aller_, an expedient to which a mind must have
recourse when it lacks power and scope to hold all experience in hand
and to view the wide world in its genuine immediacy. As oblivescence is
a gradual death, proper to a being not ideally master of the universal
flux, but swamped within it, so science is an artificial life, in which
what cannot be perceived directly (because personal limitations forbid)
may be regarded abstractly, yet efficaciously, in what we think and do.
With better faculties the field of possible experience could be better
dominated, and fewer of its parts, being hidden from sight, would need
to be mapped out symbolically on that sort of projection which we call
scientific inference. The real relations between the parts of nature
would then be given in intuition, from which hypothesis, after all, has
borrowed its schemata.

[Sidenote: Its intellectual essence.]

Science is a half-way house between private sensation and universal
vision. We should not forget to add, however, that the universal vision
in question, if it were to be something better than private sensation or
passive feeling in greater bulk, would have to be i