f-contradictory, because all
we know of the order of nature is derived from our observation of the
course of events of which the so-called miracle is a part. On the other
hand, no event is too extraordinary to be impossible; and, therefore, if
by the term miracles we mean only "extremely wonderful events," there
can be no just ground for denying the possibility of their occurrence.

But when we turn from the question of the possibility of miracles,
however they may be defined, in the abstract, to that respecting the
grounds upon which we are justified in believing any particular miracle,
Hume's arguments have a very different value, for they resolve
themselves into a simple statement of the dictates of common
sense--which may be expressed in this canon: the more a statement of
fact conflicts with previous experience, the more complete must be the
evidence which is to justify us in believing it. It is upon this
principle that every one carries on the business of common life. If a
man tells me he saw a piebald horse in Piccadilly, I believe him without
hesitation. The thing itself is likely enough, and there is no
imaginable motive for his deceiving me. But if the same person tells me
he observed a zebra there, I might hesitate a little about accepting his
testimony, unless I were well satisfied, not only as to his previous
acquaintance with zebras, but as to his powers and opportunities of
observation in the present case. If, however, my informant assured me
that he beheld a centaur trotting down that famous thoroughfare, I
should emphatically decline to credit his statement; and this even if he
were the most saintly of men and ready to suffer martyrdom in support of
his belief. In such a case, I could, of course, entertain no doubt of
the good faith of the witness; it would be only his competency, which
unfortunately has very little to do with good faith or intensity of
conviction, which I should presume to call in question.

Indeed, I hardly know what testimony would satisfy me of the existence
of a live centaur. To put an extreme case, suppose the late Johannes
Mueller, of Berlin, the greatest anatomist and physiologist among my
contemporaries, had barely affirmed he had seen a live centaur, I should
certainly have been staggered by the weight of an assertion coming from
such an authority. But I could have got no further than a suspension of
judgment. For, on the whole, it would have been more probable that even
he