understanding is strong in a single abstract principle and with this lever
moves mankind. Few attain to a balance of principles or recognize truly
how in all human things there is a thesis and antithesis, a law of action
and of reaction. In politics we require order as well as liberty, and have
to consider the proportions in which under given circumstances they may be
safely combined. In religion there is a tendency to lose sight of
morality, to separate goodness from the love of truth, to worship God
without attempting to know him. In philosophy again there are two opposite
principles, of immediate experience and of those general or a priori truths
which are supposed to transcend experience. But the common sense or common
opinion of mankind is incapable of apprehending these opposite sides or
views--men are determined by their natural bent to one or other of them;
they go straight on for a time in a single line, and may be many things by
turns but not at once.

Hence the importance of familiarizing the mind with forms which will assist
us in conceiving or expressing the complex or contrary aspects of life and
nature. The danger is that they may be too much for us, and obscure our
appreciation of facts. As the complexity of mechanics cannot be understood
without mathematics, so neither can the many-sidedness of the mental and
moral world be truly apprehended without the assistance of new forms of
thought. One of these forms is the unity of opposites. Abstractions have
a great power over us, but they are apt to be partial and one-sided, and
only when modified by other abstractions do they make an approach to the
truth. Many a man has become a fatalist because he has fallen under the
dominion of a single idea. He says to himself, for example, that he must
be either free or necessary--he cannot be both. Thus in the ancient world
whole schools of philosophy passed away in the vain attempt to solve the
problem of the continuity or divisibility of matter. And in comparatively
modern times, though in the spirit of an ancient philosopher, Bishop