and uncorrupt
judge, whose mind is not made thereby the more active or discriminating,
nor his decision brought into closer accordance with the facts as they are
presented to him. Knowledge is indeed an indispensable auxiliary to
conscience; but this cannot be affirmed exclusively of any specific
department of knowledge. It is true of all knowledge; for there is no fact
or law in the universe that may not in some contingency become the
subject-matter or the occasion for the action of conscience. Nothing could
seem more remote from the ordinary field of conscience than the theory of
planetary motion; yet it was this that gave Galileo the one grand
opportunity of his life for testing the supremacy of conscience,--it may
be, the sole occasion on which his conscience uttered itself strongly
against his seeming interest, and one on which obedience to conscience
would have averted the only cloud that ever rested on his fame.

Section II.

Sources Of Knowledge. 1. Observation, Experience, And Tradition.

Except so far as there may have been direct communications from the
Supreme Being, all *man's knowledge* of persons, objects, and relations
*is derived*, in the last resort, *from observation*. Experience is merely
remembered self-observation. Tradition, oral and written, is accumulated
and condensed observation; and by means of this each new generation can
avail itself of the experience of preceding generations, can thus find
time to explore fresh departments of knowledge, and so transmit its own
traditions to the generations that shall follow. Now what we observe in
objects is chiefly their properties, or, what is the same thing, their
_fitnesses_; for a property is that which fits an object for a specific
place or use. What we observe in persons is their relations to other
beings and objects, with the fitnesses that belong to those relations.
What we experience all resolves itself into the fitness or unfitness of
persons and objects to one *another* or to ourselves. What is transmitted
in history and in science is the record of fitnesses or unfitnesses that
have been ascertained by observation, or tested by experience. The
progress of knowledge is simply an enlarged acquaintance with the
fitnesses of persons and things. He knows the most, who most fully
comprehends the relations in which the beings and objects in the universe
stand, have stood, and ought to stand toward one another