lly a dread of Nature, and
of the powers thereof. For when the authority of great names has
reigned unquestioned for many centuries, those names become, to the
human mind, integral and necessary parts of Nature itself. They
are, as it were, absorbed into it; they become its laws, its canons,
its demiurges, and guardian spirits; their words become regarded as
actual facts; in one word, they become a superstition, and are
feared as parts of the vast unknown; and to deny what they have said
is, in the minds of the many, not merely to fly in the face of
reverent wisdom, but to fly in the face of facts. During a great
part of the Middle Ages, for instance, it was impossible for an
educated man to think of nature itself, without thinking first of
what Aristotle had said of her. Aristotle's dicta were Nature; and
when Benedetti, at Venice, opposed in 1585 Aristotle's opinions on
violent and natural motion, there were hundreds, perhaps, in the
universities of Europe--as there certainly were in the days of the
immortal "Epistolae Obscurorum Virorum"--who were ready, in spite of
all Benedetti's professed reverence for Aristotle, to accuse him of
outraging not only the father of philosophy, but Nature itself and
its palpable and notorious facts. For the restoration of letters in
the fifteenth century had not at first mended matters, so strong was
the dread of Nature in the minds of the masses. The minds of men
had sported forth, not toward any sound investigation of facts, but
toward an eclectic resuscitation of Neoplatonism; which endured, not
without a certain beauty and use--as let Spenser's "Faerie Queen"
bear witness--till the latter half of the seventeenth century.

After that time a rapid change began. It is marked by--it has been
notably assisted by--the foundation of our own Royal Society. Its
causes I will not enter into; they are so inextricably mixed, I
hold, with theological questions, that they cannot be discussed
here. I will only point out to you these facts: that, from the
latter part of the seventeenth century, the noblest heads and the
noblest hearts of Europe concentrated themselves more and more on
the brave and patient investigation of physical facts, as the source
of priceless future blessings to mankind; that the eighteenth
century which it has been the fashion of late to depreciate, did
more for the welfare of mankind, in every conceivable direction,
than the whole fifteen centuries before it; t