to be, to know, and to do--desires that short of infinity can never be
satisfied, as they grow by what they feed on.

Mind is the instrument by which man advances, and by which each advance
is secured and made the vantage ground for new advances. Though he may
not by taking thought add a cubit to his stature, man may by taking
thought extend his knowledge of the universe and his power over it, in
what, so far as we can see, is an infinite degree. The narrow span of
human life allows the individual to go but a short distance, but though
each generation may do but little, yet generations, succeeding to the
gain of their predecessors, may gradually elevate the status of mankind,
as coral polyps, building one generation upon the work of the other,
gradually elevate themselves from the bottom of the sea.

Mental power is, therefore, the motor of progress, and men tend to
advance in proportion to the mental power expended in progression--the
mental power which is devoted to the extension of knowledge, the
improvement of methods, and the betterment of social conditions.

Now mental power is a fixed quantity--that is to say, there is a limit
to the work a man can do with his mind, as there is to the work he can
do with his body; therefore, the mental power which can be devoted to
progress is only what is left after what is required for non-progressive
purposes.

These non-progressive purposes in which mental power is consumed may be
classified as maintenance and conflict. By maintenance I mean, not only
the support of existence, but the keeping up of the social condition and
the holding of advances already gained. By conflict I mean not merely
warfare and preparation for warfare, but all expenditure of mental power