We ought not, however, to carry these conclusions too far, for every problem has its relative bearings, and positive observation, unlike logic, does not admit simple and exact solutions. It must be observed that this idea of artificial selection, though true, would lead to exaggerated conclusions, if it were carried into the sociological field without reserve, and without the necessary balance between the interests and rights of the community and of individuals. If this idea were taken absolutely, indeed, it would render legitimate and even obligatory an ultra-Spartan elimination of all children born abortive or incurably diseased, or anti- social through their idiotcy or mental insanity. On the other hand, to recognise that the death penalty may be legitimate as an extreme and exceptional measure is not to acknowledge that it is necessary in the normal conditions of social life. Now it cannot be questioned that in these normal conditions society may defend itself otherwise than by death, as <p 241>by perpetual seclusion or transportation, the failure of which, by the escape of convicts, is too rare to be decisive against it. The preventive and deterrent efficacy of the death penalty is very problematical when we examine it not by our own impressions as average human beings, calmly and theoretically, but with the data of criminal psychology, which is its only true sphere of observation. Every one who commits a crime is either carried away by sudden passion, when he thinks of nothing, or else he acts coolly and with premeditation, and then he is determined in his action, not by a dubious comparison between the death penalty and imprisonment for life, but simply by a hope of impunity. This is especially the case with born criminals, whose main psychological characteristic is an excess of improvidence, combined with moral insensibility. If a convict tells us that he fears death, this merely means that he has the momentary impression, which cannot, however, restrain him from crime, for here again, by the same psychological tendency, he will be subject only to the criminal temptation. And if it is true that, when the criminal has been tried and condemned, he fears death more than imprisonment for life (always excepting condemned suicides, and those who by their physical and moral insensibility laugh at death up to the foot of the scaffold), it is none the less necessary to try and to condemn them.