The grades of imbecility can not be clearly marked off from one another, but, roughly speaking, there are three. The lowest grade of imbeciles understands simple commands, and has a slight manual dexterity. They express themselves by signs and in monosyllables. They can not concentrate attention upon anything, nor can they be taught to read or write. Careful training can advance them so far that they may do rough, menial work, and they are industrious when directed by a present superior. They are inclined to masturbation. If they are not teased, they are quiet; if annoyed, they may become dangerous. Imbeciles of the middle grade can converse in a narrow vocabulary, and they commonly stammer. They may be taught to read monosyllables; they can not do even the simplest sum in addition, yet they show a certain shrewdness. They are irritable and quarrelsome, inclined to lying and stealing, and they have no sense of shame. They will not do any regular work, but change from one occupation to another. They may have sexual instincts and cause trouble on that account. They are slow to understand, their memories are defective, and they are always very vain. Their belly and what they shall wear are the chief things in their lives. They are less criminal than the highest grade of imbeciles. The third class, the high-grade imbecile, is the most important, because he is commonly a criminal. His intellect is below the average, and his will is very flabby. He learns little at school, and what he does learn is acquired slowly. He reads and writes badly and he may be able to add simple {115} columns of numbers, but he can not multiply or divide. Sometimes such an imbecile has a remarkable facility in getting a speaking knowledge of two or three languages, and he may learn a trade. There is a high-grade imbecile that is cunning and shrewd, but he has no will, and he is a criminal. As imbeciles approach the normal in intellect they recede from it in abnormality of will. Autopsies on imbeciles show an infantile development of the forebrain. Imprisonment does no good in these cases. They are not taught anything in prison, not even a trade, because the labour organisations and the protected industries will not permit prison labour. They should be confined so that they will not pervert youth and propagate their kind. It is impossible to say how far a given imbecile is morally accountable for what he does, but the accountability is not full in the best cases. A neurasthenic, however, is not to be mistaken for an imbecile. A neurasthenic person may have a tender conscience, an imbecile has no conscience. In imbecility the fault is in the will, rather than in the intellect, in the middle and highest grades. Many women, especially, that are hopeless fools intellectually have strong wills, but an imbecile never has a strong will except in the sense that stubbornness is strength. Stubbornness is perverted strength.