His intelligence does not grow with his body.

Society pities him if he be without natural protection, and puts him away in an institution.

So of the insane, the pronounced lunatic; he varies too much to sustain in any way the wide system of social relationships which society requires of each individual.

Either he is unable to take care of himself, or he attempts the life of some one else, or he is the harmless, unsocial thing that wanders among us like an animal or stands in his place like a plant.

He is not a factor in social life; he has not come into the inheritance.
Then there is the extraordinary class of people whom we may describe by a stronger term than those already employed.