leaping back into life even more monstrous and irrational than in
past ages, and to see our modern Pharisees and Sadducees, like those
in Judea of old, seeking after a sign of an unseen world; and being
unable to find one either in the heaven above or in the earth
beneath, discovering it at last (I am almost ashamed to speak the
words) under the parlour-table.

Against such extravagances, and against the loose sentimental tone
of mind which begets them, hardly anything would be a better
safeguard than the habitual study of nature. The chemist, the
geologist, the botanist, the zoologist, has to deal with facts which
will make him master of them, and of himself, only in proportion as
he obeys them. Many of you doubtless know Lord Bacon's famous
apothegm, Nature is only conquered by obeying her; and will
understand me when I say, that you cannot understand, much less use
for scientific purposes, the meanest pebble, unless you first obey
that pebble. Paradoxical; but true.

See this pebble which I hold in my hand, picked up out of the street
as I came along; it shall be my only object to-night. There the
thing is; and is as it is, and in no other way; and such it will be,
and so it will behave and act, in spite of me, and all my fancies
about it, and notions of what it ought to have been like, and what
it ought to have done. It is a thought of God's; and strong by the
eternal laws of matter, which are the will of God. It has the whole
universe, sun, and stars, and all, backing it by God's appointment,
to keep it where it is and what it is; and till (as Lord Bacon has
it) I have discovered and obeyed the will of God revealed in that
pebble, it is to me a riddle more insoluble than the Sphinx's, a
fortress more impregnable than Sevastopol. I may crush it: but