erests him less. The rule laid
down by the late Mr. Spedding, "When a thing is asserted as a fact,
always ask who first reported it, and what means he had of knowing the
truth," is an admirable corrective of loose traditional stories.

A further test has to be applied by each investigator for himself. When
we have ascertained, as far as possible, on what evidence our knowledge
of an alleged fact rests, we have to consider the inherent probability
of the allegation. Is the statement about it in accordance with the
general workings of human nature, or with the particular working of the
nature of the persons to whom the action in question is ascribed? Father
Gerard,[18] for instance, lavishly employs this test. Again and again he
tells us that such and such a statement is incredible, because, amongst
other reasons, the people about whom it was made could not possibly have
acted in the way ascribed to them. If I say in any of these cases that
it appears to me probable that they did so act, it is merely one
individual opinion against another. There is no mathematical certainty
on either side. All we can respectively do is to set forth the reasons
which incline us to one opinion or another, and leave the matter to
others to judge as they see fit.

It will be necessary hereafter to deal at length with father Gerard's
attack upon the evidence, hitherto accepted as conclusive, of the facts
of the plot. A short space may be allotted to the reasons for rejecting
his preliminary argument, that it was the opinion of some
contemporaries, and of some who lived in a later generation, that
Salisbury contrived the plot in part, if not altogether. Does he realize
how difficult it is to prove such a thing by any external evidence
whatever? If hearsay evidence can be taken as an argument of
probability, and in some cases of strong probability, it is where some
one material fact is concerned. For instance, I am of opinion that it is
very likely that the story of Cromwell's visit to the body of Charles I
on the night after the king's execution is true, though the evidence is
only that Spence heard it from Pope, and Pope heard it, mediately or
immediately, from Southampton, who, it is alleged, saw the scene with
his own eyes. It is very different when we are concerned with evidence
as to an intention necessarily kept secret, and only exhibited by overt
acts in such form as tampering with documents, suggesting false
explanation of evidence, an