108 JOURNAL OF SCIENCE. 
be no science of history because we cannot be sure of our data. 
No doubt the evidence on which history rests is often confused 
and contradictory, and has sometimes been intentionally falsified, 
but the main facts are certain enough. And are not the facts 
often confused and contradictory in natural science? Have we 
not even falsifications in nature? The resemblance of a whale 
to a fish deceived even the great Linnzus, and the resemblance 
of the eye of the cuttle-fish to that of a vertebrate has misled 
later naturalists. The inversion of strata has often misled 
geologists, and all the phenomena of mimetic resemblances are 
in a sense falsifications. Intentional deception may be more 
difficult to detect, but ifit had not been possible to detect forgeries 
we should not know that any had been committed. That the 
science of history is difficult will be allowed, but that does not 
make it impossible. 
Mr. Froude believes that there can be no science of history, 
because human beings have free-will. He says, “When natural 
causes are liable to be set asideand neutralised by what is called 
volition, the word science is out of place.” But in all sciences 
one cause may be neutralised by another, and volition is, as we 
have seen, the cause of mental variations, without which selection 
could not act. A science of history can exist without a know- 
ledge of the origin of ideas, although, of course, without that 
knowledge it would be incomplete. This, indeed, was pointed 
out by Kant a hundred years ago, although he could not explain 
it. ‘“ Whatsoever difference,” he says, “there may be in our 
notions of freedom of the will, metaphysically considered, it is 
evident that the manifestations of that will, viz., human actions, 
are as much under the control of universal laws of nature as any 
other physical phenomena.’* We might as well say that there 
can be no science of biology, because structural variation obeys 
no known law. No doubt it makes prediction very difficult, or 
even impossible, except in a general way, but it does not follow 
that there is no science of biology. The idea that the power of 
prediction is essential to a science was originated by Compte, as 
a corollary from the Positive Philosophy, and it has been widely 
accepted by unscientific men without much consideration. But 
if this be taken as a test, science will be reduced to those por- 
tions of astronomy and physics which are capable of being 
treated deductively by mathematical analysis. The astronomer 
cannot predict the appearance of comets; the physicist cannot 
predict the rate of expansion by heat of an untried substance ; 
the chemist cannot predict the properties of a new compound ; 
the geologist cannot predict the future physical geography of 
the earth ; but, as Mr. J. S. Mill says, “ We must remember that 
a degree of knowledge far short of the power of prediction is 
often of much practical value. There may be great power of 
influencing phenomena with a very imperfect knowledge of the 
causes by which they are in any given instance determined. It 
* 66 
Idea of Universal History,” translated by De Quincey. 
