_intrinsically
criminal_. If it were _intrinsically criminal_, it was criminal at
common law. If it was not intrinsically criminal, it was not criminal at
common law. (At least, such was the general principle of the common law.
There may have been exceptions in practice, owing to the fact that the
opinions of men, as to what was intrinsically criminal, may not have
been in all cases correct.)

A jury, then, in judging whether an accused person knew his act to be
illegal, were bound first to use their own judgments, as to whether the
act were _intrinsically_ criminal. If their own judgments told them the
act was _intrinsically_ and _clearly_ criminal, they would naturally and
reasonably infer that the accused also understood that it was
intrinsically criminal, (and consequently illegal,) unless it should
appear that he was either below themselves in the scale of intellect, or
had had less opportunities of knowing what acts were criminal. In
short, they would judge, from any and every means they might have of
judging; and if they had any reasonable doubt that he knew his act to be
criminal in itself, they would be bound to acquit him.

The second reason that has been offered for the doctrine that ignorance
of the law excuses no one, is this:

"Ignorance of the municipal law of the kingdom, or of the penalty
thereby inflicted on offenders, doth not excuse any that is of the
age of discretion and compos mentis, from the penalty of the breach
of it; because every person, of the age of discretion and compos
mentis, _is bound to know the law_, and presumed to do so.
_Ignorantia eorum, quae quis scire tenetur non excusat_." (Ignorance
of those things which every one is bound to know, does not
excuse.)--_1 Hale's Pleas of the Crown_, 42. _Doctor and Student,
Dialog. 2_, ch. 46. _Law Magazine_, (_London_,) vol. 27, p. 97.

The sum of this reason is, that ignorance of the law excuses no one,
(who is of the age of discretion and is compos mentis,) because every
such person "_is bound to know the law_." But this is giving no reason
at all for the doctrine, since saying that a man "is bound to know the
law," is only saying, _in another form_, that "ignorance of the law does
not excuse him." There is no difference at all in the two ideas. To say,
therefore, that "ignorance of the law excuses no one, _because_ every
one is bound to know the law," is only equivalent to saying that
"ignorance of the law ex