idea then (and a great deal of that ancient conception still remains)
that there was a sort of essential antithesis, not to say antagonism,
between nature and man; and that the two had not very much to do with
one another, except that the one was oftentimes exceedingly troublesome
to the other. Though it is one of the salient merits of our great
philosophers of the seventeenth century, that they recognised but one
scientific method, applicable alike to man and to nature, we find this
notion of the existence of a broad distinction between nature and man
in the writings both of Bacon and of Hobbes of Malmesbury; and I have
brought with me that famous work which is now so little known, greatly
as it deserves to be studied, "The Leviathan," in order that I may put
to you in the wonderfully terse and clear language of Thomas Hobbes,
what was his view of the matter. He says:--

"The register of knowledge of fact is called history. Whereof there be
two sorts, one called natural history; which is the history of such
facts or effects of nature as have no dependence on man's will; such as
are the histories of metals, plants, animals, regions, and the like.
The other is civil history; which is the history of the voluntary
actions of men in commonwealths."

So that all history of fact was divided into these two great groups of
natural and of civil history. The Royal Society was in course of
foundation about the time that Hobbes was writing this book, which was
published in 1651; and that Society was termed a "Society for the
Improvement of Natural Knowledge," which was then nearly the same thing
as a "Society for the Improvement of Natural History." As time went on,
and the various branches of human knowledge became more distinctly
developed and separated from one another, it was found that some were
much more susceptible of precise mathematical treatment than others.