for in itself it is the record of the growth of those ideas that
have made our race and its civilization what they are; of ideas
instinct with human interest, vital with meaning for our race;
fundamental in their influence on human development; part and
parcel of the mechanism of human thought on the one hand, and of
practical civilization on the other. Such a phrase as
"fundamental principles" may seem at first thought a hard saying,
but the idea it implies is less repellent than the phrase itself,
for the fundamental principles in question are so closely linked
with the present interests of every one of us that they lie
within the grasp of every average man and woman--nay, of every
well-developed boy and girl. These principles are not merely the
stepping-stones to culture, the prerequisites of knowledge--they
are, in themselves, an essential part of the knowledge of every
cultivated person.

It is our task, not merely to show what these principles are, but
to point out how they have been discovered by our predecessors.
We shall trace the growth of these ideas from their first vague
beginnings. We shall see how vagueness of thought gave way to
precision; how a general truth, once grasped and formulated, was
found to be a stepping-stone to other truths. We shall see that
there are no isolated facts, no isolated principles, in nature;
that each part of our story is linked by indissoluble bands with
that which goes before, and with that which comes after. For the
most part the discovery of this principle or that in a given
sequence is no accident. Galileo and Keppler must precede Newton.
Cuvier and Lyall must come before Darwin;--Which, after all, is
no more than saying that in our Temple of Science, as in any
other piece of architecture, the foundation must precede the