Similarly the hereditarily insane and epileptic can best be cared for through life-long segregation—a course which society is likely to adopt readily, because of a general dread of having insane and epileptic persons at liberty in the community. There are undoubtedly cases where the relatives of the affected individual can and should assume responsibility for his care. No insane or epileptic person whose condition is probably of a hereditary character should be allowed to leave an institution unless it is absolutely certain that he or she will not become a parent: if sterilization is the only means to assure this, then it should be used. In many cases it has been found that the individual and his relatives welcome such a step.
The habitual criminals, the chronic alcoholics, and the other defectives whom we have mentioned as being undesirable parents, will in most cases need to be given institutional care throughout life, in their own interest as well as that of society. This is already being done with many of them, and the extension of the treatment involves no new principle nor special difficulty.
It should be borne in mind that, from a eugenic point of view, the essential element in segregation is not so much isolation from society, but separation of the two sexes. Properly operated, segregation increases the happiness of the individuals segregated, as well as working to the advantage of the body politic. In most cases the only objection to it is the expense, and this, as we have shown, need not be an insuperable difficulty. For these reasons, we believe that segregation is the best way in which to restrict the reproduction of those whose offspring could hardly fail to be undesirable, and that sterilization should be looked upon only as an adjunct, to be used in special cases where it may seem advantageous to allow an individual full liberty, or partial liberty, and yet where he or she can not be trusted to avoid reproduction.