lt of pushing our inquiries so far may seem to be
to show that we really know nothing at all. But in truth the
uncertainty is no greater than the uncertainty which attends all
inquiries in the historical sciences. Though a historical fact may be
recorded in the most trustworthy documents, though it may have happened
in our own times, though we may have seen it happen with our own eyes,
yet we cannot have the same certainty about it as the mathematician has
about the proposition which he proves to absolute demonstration. We
cannot have even that lower degree of certainty which the geologist has
with regard to the order of succession between this and that stratum.
For in all historical inquiries we are dealing with facts which
themselves come within the control of human will and human caprice, and
the evidence for which depends on the trustworthiness of human
informants, who may either purposely deceive or unwittingly mislead. A
man may lie; he may err. The triangles and the rocks can neither lie
nor err. I may with my own eyes see a certain man do a certain act; he
may tell me himself, or some one else may tell me, that he is the same
man who did some other act; but as to his statement I cannot have
absolute certainty, and no one but myself can have absolute certainty
as to the statement which I make as to the facts which I saw with my
own eyes. Historical evidence may range through every degree, from the
barest likelihood to that undoubted moral certainty on which every man
acts without hesitation in practical affairs. But it cannot get beyond
this last standard. If, then, we are ever to use words like race,
family, or even nation, to denote groups of mankind marked off by any
kind of historical, as distinguished from physical, characteristics, we
must be content to use those words, as we use many other words, without
being able to prove that our use of them is accurate, as mathematicians
judge of accuracy. I cannot be quite sure that William the Conqueror
landed at Pevensey, though I have strong reasons for believing that he
did so. And I have strong reasons for believing many facts about race
and language about which I am much further from being quite sure than I
am about William's landing at Pevensey. In short, in all these
matters, we must be satisfied to let presumption very largely take the
place of actual proof; and, if we only let presumption in, most of our
difficulties at once fly away. Language is