476 
Is this so? 
We may begin to doubt it when we reflect 
that the triumphs of science which bring 
these material advantages are in their very 
nature intellectual triumphs. The increas- 
ing benefits brought by science are the re- 
sults of man’s increasing mastery over Na- 
ture, and that mastery is increasingly a 
mastery of mind; it is an increasing power 
to use the forces of what we call inanimate 
nature in place of the force of his own or 
other creatures’ bodies; it is an increasing 
use of mind in place of muscle. 
Is it to be thought that that which has 
brought the mind so greatly into play has 
had no effect on the mind itself? Is that 
part of the mind which works out scientific 
truths a mere slavish machine producing 
results it knows not how, having no part in 
the good which in its working it brings 
forth? 
What are the qualities, the features of 
that scientific mind which has wrought, and 
is working, such great changes in man’s re- 
lation to Nature? In seeking an answer to 
this question we have not to inquire into 
the attributes of genius. Though much of 
the progress of science seems to take on the 
form of a series of great steps, each made 
by some great man, the distinction in sci- 
ence between the great discoverer and the 
humble worker is one of degree only, not 
of kind. As I was urging just now, the 
greatness of many great names in science 
is often, in large part, the greatness of occa- 
sion, not of absolute power. The qualities 
which guide one man to a small truth 
silently taking its place among its fellows, 
as these go to make up progress, are at bot- 
tom the same as those by which another 
man is led to something of which the whole 
world rings. 
The features of the fruitful scientific 
mind are in the main three. 
In the first place, above all other things, 
his nature must be one which vibrates in 
SCIENCE. 
(N.S. Vou. X. No. 249. 
unison with that of which he is in search; 
the seeker after truth must himself be 
truthful, truthful with the truthfulness of 
Nature. For the truthfulness of Nature is 
not wholly the same as that which man 
sometimes calls truthfulness. It is far 
more imperious, far more exacting. Man, 
unscientific man, is often content with ‘ the 
nearly’ and ‘the almost.’ Nature never 
is. It is not her way to call the same two 
things which differ, though the difference 
may be measured by less than a thousandth 
of a milligram or of a millimeter, or by 
any other like standard of minuteness. 
And the man who, carrying the ways of 
the world into the domain of science, thinks 
that he may treat Nature’s differences in 
any other way than she treats them her- 
self, will find that she resents his conduct ; 
if he in carelessness or in disdain overlooks 
the minute difference which she holds out 
to him as a signet to guide him in his 
search, the projecting tip, as it were, of 
some buried treasure, he is bound to go 
astray, and the more strenuously he strug- 
gles on, the farther will he find himself 
from his true goal. 
In the second place, he must be alert of 
mind. Nature is ever making signs to us, 
she is ever whispering to us the beginnings 
of her secrets; the scientific man must be 
ever on the watch, ready at once to lay 
hold of Nature’s hint, however small, to 
listen to her whisper however low. 
In the third place, scientific inquiry, 
though it be preéminently an intellectual 
effort, has need of the moral quality or 
courage—not so much the courage which 
helps a man to face a sudden difficulty as 
the courage of steadfast endurance. Al- 
most every inquiry, certainly every pro- 
longed inquiry, sooner or later goes wrong. 
The path, at first so straight and clear, 
grows crooked and gets blocked; the hope 
and enthusiasm, or even the jaunty ease, 
with which the inquirer set out, leave him 
