But this account of the matter is at least questionable. So far as the use of words goes, I am not aware that consideration is distinctly called cause before the reign of Elizabeth; in the earlier reports it always appears as quid pro quo. Its first appearance, so far as I know, is in Fleta's account of the action of debt, /1/ and although I am inclined to believe that Fleta's statement is not to be trusted, a careful consideration of the chronological order of the cases in the Year Books will show, I think, that the doctrine was fully developed in debt before any mention of it in equity can be found. One of the earliest [254] references to what a promisor was to have for his undertaking was in the action of assumpsit. /1/ But the doctrine certainly did not originate there. The first mention of consideration in connection with equity which I have seen is in the form of quid pro quo, /2/ and occurs after the requirement had been thoroughly established in debt. /3/ The single fact that a consideration was never required for contracts under seal, unless Fleta is to be trusted against the great weight of nearly contemporaneous evidence, goes far to show that the rule cannot have originated on grounds of policy as a rule of substantive law. And conversely, the coincidence of the doctrine with a peculiar mode of procedure points very strongly to the probability that the peculiar requirement and the peculiar procedure were connected. It will throw light on the question to put together a few undisputed facts, and to consider what consequences naturally followed. It will therefore be desirable to examine the action of debt a little further. But it is only fair to admit, at the outset, that I offer the explanation which follows with great hesitation, and, I think, with a full appreciation of the objections which might be urged. It was observed a moment ago, that, in order to recover against a defendant who denied his debt, the plaintiff had to show something for it; otherwise he was turned over to the limited jurisdiction of the spiritual tribunals. /4/ This requirement did not mean evidence in the modern sense. It meant simply that he must maintain his cause in one of the ways then recognized by law. These were three, the [255] duel, a writing, and witnesses. The duel need not be discussed, as it soon ceased to be used in debt, and has no bearing on what I have to say. Trial by writing and by witnesses, on the other hand, must both be carefully studied. It will be convenient to consider the latter first and to find out what these witnesses were.