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 excuses no one, _because_ ignorance of the law excuses no one." It is merely reässerting the doctrine, without giving any reason at all. And yet these reasons, which are really no reasons at all, are the only ones, so far as I know, that have ever been offered for this absurd and brutal doctrine. The idea suggested, that "the age of discretion" determines the guilt of a person,--that there is a particular age, prior to which _all_ persons alike should be held incapable of knowing _any_ crime, and subsequent to which _all_ persons alike should be held capable of knowing _all_ crimes,--is another of this most ridiculous nest of ideas. All mankind acquire their knowledge of crimes, as they do of other things, _gradually_. Some they learn at an early age; others not till a later one. One individual acquires a knowledge of crimes, as he does of arithmetic, at an earlier age than others do. And to apply the same presumption to all, on the ground of age alone, is not only gross injustice, but gross folly. A universal presumption might, with nearly or quite as much reason, be founded upon weight, or height, as upon age.[103]