n to evidence derived from
such experiments as have been found possible, and as a supplement to
the experience out of which, as out of a nucleus, every conception must
grow, the mind is set to design and invent a self-coherent scheme which
shall imitate as far as possible the results exhibited by nature. By
then using this as a working hypothesis, and pressing it into extremes,
it can be gradually amended until it shows no sign of discordance or
failure anywhere, and even serves as a guide to new and previously
unsuspected phenomena. When that stage is reached, it is provisionally
accepted and tentatively held as a step in the direction of the truth;
though the mind is always kept ready to improve and modify and enlarge
it, in accordance with the needs of more thorough investigation and
fresh discovery. It was so, for instance, with Maxwell's
electromagnetic theory of light; and there are a multitude of other
instances.

In the transcendental or ultra-mundane or supersensual region there is
the further difficulty to be encountered, that we are not acquainted
with anything like all the 'boundary conditions,' so to speak; we only
know our little bit of the boundary, and we may err egregiously in
inferring or attempting to infer the remainder. We may even make a
mistake as to the form of function adapted to the case. Nevertheless
there is no better clue, and the human mind is impelled to do the best
it can with the confessedly imperfect data which it finds at its
disposal. The result, therefore, in this region, is no system of
definite and certain truth, as in Physics, but is either suspense of
judgment altogether, or else a tentative scheme or working hypothesis,
to be held undogmatically, in an attitude of constant receptiveness for
further light, and in full readiness for modification in the direction
of the truth.

So far concerning the ascertainment of truth alone, in intangible
regions of inquiry. The further hypothesis that such truth when found
will be most satisfactory, or in other words higher and better than any
alternative plan,--the conviction that faith in the exceeding grandeur
of reality shall not be confounded,--requires further justification;
and its grounds are not so easy to formulate. Perhaps the feeling is
merely human and instinctive; but it is existent and customary I
believe among physicists, possibly among men of Science in general,
though I cannot speak for all; and it must be based upon famili