Here Dr. Whately is exercising his red biro on Mr. Hume in the matter of distribution. The latter has treated (some) testimony as though it were any testimony whatever.
There is an argument against miracles by the well-known Mr. Hume, which has perplexed many persons, and which exactly corresponds to the above. It may be stated thus: “Testimony is a kind of evidence more likely to be false, that a miracle to be true; “ (or, as it may be expressed in other words, we have reason to expect that a witness should lie, than that a miracle should occur) “ the evidence on which the Christian miracles are believed, is testimony; therefore the evidence on which the Christian miracles are believed is more likely to be false than a miracle is to be true.”(from Elements of Logic Bk.1 Section 4 )
Here it is evident that what is spoken of in the first of these Premises, is, “some testimony; not “all testimony,” (or any whatever,) and by “a witness” we understand “some witness,” not, “every witness”: so that this apparent argument has exactly the same fault as the one above.