=Institutional Figures Misleading.--=However, significant as are these figures from institutions for delinquents, one should not be misled by them. They are undoubtedly not representative of offenders in general, but of a selected group of the most hopeless cases. In the first place the more capable individuals escape the dragnet which lands the defective delinquents in an institution, and furthermore, because of liberal systems of probation, only the more incorrigible or the very stupid make up the bulk of the population of such places. Miss Augusta F. Bronner, assistant director of the Psychopathic Institute of the Juvenile Court of Chicago, from a careful study of five hundred and five cases of delinquent boys and girls in the Detention Home, chosen with as little selection as possible, finds the proportion of mentally subnormal among them to be less than ten per cent. =Many Prisoners Mentally Subnormal.--=Doctor Walter S. Fernald, of the Massachusetts School for Feeble-minded, estimates that "at least 25 per cent. of the inmates of our penal institutions are mentally defective." Among the various available estimates at hand this seems to be a fairly conservative approximation. Hastings H. Hart points out that this calculation of 25 per cent. means that there are 20,000 adult defective delinquents in prison, and 6,000 youths in juvenile reformatories, or a total of 26,000 in custody in the United States. =The Inhibitions Necessary to Social Welfare Not Well Established in All.--=But let us look at this matter of delinquency a little more in detail. In common with other living creatures mankind has two strongly predominating instincts without which there can be no prolonged individual or racial existence, namely, the self-preservative and the reproductive. Says Schiller: "While philosophers are disputing about the government of the world, Hunger and Love are performing the task." Under self-preservative would be included everything pertaining to food, property and self-protection. In addition, however, man, together with certain other social animals, has developed a third set of activities or instincts--an impulsion toward the preservation of the community to which he belongs--and so far has this evolved in his case that it outranks in importance the other two. For the highest accomplishments and ideals of the race are in last analysis expressions of this social instinct. But with this system of mutual help comes the necessity of certain restraints, because for society to exist its members must impose upon themselves, or have imposed upon them, certain inhibitions of their self-preservative and reproductive instincts.