ff himself was a slave at the time of action
brought, is a substantive fact, having no necessary connection with
the fact that his parents were sold as slaves. For they might have
been sold after he was born; or the plaintiff himself, if once a
slave, might have became a freeman before action brought. To aver
that his ancestors were sold as slaves, is not equivalent, in point of
law, to an averment that he was a slave. If it were, he could not even
confess and avoid the averment of the slavery of his ancestors, which
would be monstrous; and if it be not equivalent in point of law, it
cannot be treated as amounting thereto when demurred to; for a
demurrer confesses only those substantive facts which are well
pleaded, and not other distinct substantive facts which might be
inferred therefrom by a jury. To treat an averment that the
plaintiff's ancestors were Africans, brought to this country and sold
as slaves, as amounting to an averment on the record that he was a
slave, because it may lay some foundation for presuming so, is to hold
that the facts actually alleged may be treated as intended as evidence
of another distinct fact not alleged. But it is a cardinal rule of
pleading, laid down in Dowman's case, (9 Rep., 9 b,) and in even
earlier authorities therein referred to, "that evidence shall never be
pleaded, for it only tends to prove matter of fact; and therefore the
matter of fact shall be pleaded." Or, as the rule is sometimes stated,
pleadings must not be argumentative. (Stephen on Pleading, 384, and
authorities cited by him.) In Com. Dig., Pleader E. 3, and Bac.
Abridgement, Pleas I, 5, and Stephen on Pl., many decisions under this
rule are collected. In trover, for an indenture whereby A granted a
manor, it is no plea that A did not grant the manor, for it does not
answer the declaration except by argument. (Yelv., 223.)

So in trespass for taking and carrying away the plaintiff's goods, the
defendant pleaded that the plaintiff never had any goods. The court
said, "this is an infallible argument that the defendant is not
guilty, but it is no plea." (Dyer, a 43.)

In ejectment, the defendant pleaded a surrender of a copyhold by the
hand of Fosset, the steward. The plaintiff replied, that Fosset was
not steward. The court held this no issue, for it traversed the
surrender only argumentatively. (Cro. Elis., 260.)

In these cases, and many others reported in the books, the inferences
from the facts stated were i