Quite aside from all this it is not certain that intelligent people are necessarily safer to the community than stupid ones.  There is always a tendency for the stupid to stick to the beaten path.  Intelligence generally means individuality and divergence.  On the other hand, the stupid and subnormal are moved much more directly by instincts and emotions.  Their lack of imagination, poor perceptions and want of reasoning or comparing power, make their self-control weak.  In sudden stress or an unusual situation, they are easily swept away and respond directly to instinct and feeling.  In short the urge of the primitive through the long history of the race cannot be modified sufficiently by the new structure that civilization has built around more intelligent people.

The various distinctions between the feeble-minded and the normal must not be taken with too much confidence.  As the motives that govern man are understood, it is easy to see that intelligence is a strong factor in regulating behavior.  When it is seen also that at least the larger part of the inmates of prisons are subnormal and at the same time without property or education, it is evident that all these handicaps are dominating causes of conduct.  This position is made still more certain by the further evidence that nearly all of the repeaters in prison are of this type.

Most states already make some allowances in their criminal codes for the defective and the insane.  This is really an acknowledgment that the activity of the human machine is governed by its make and environment.  The history of the treatment of the insane serves to show the uncertainty of all man’s theories as to punishment and responsibility.  Doubtless at a very early age in the history of man it was discovered that there were people who acted so abnormally that they could not be classified with the great mass.  Such persons were supposed to be possessed of devils or demons, and various incantations and practices were used to drive the devils out.  Failing in this they were put in prison, loaded with chains or put to death because of their danger to the community.

In other communities, however, insane persons were thought to be possessed of special gifts.  God had come nearer to them than to common mortals, and they were seers or prophets endowed with a portion of the divine power.

Either view of the problem is explainable by the lack of scientific or exact knowledge that marks early societies.  Still these societies relied on punishments just as much as our present law-makers and enforcers, possibly more, because presumably less enlightened.  Further investigation and experiences with the insane have convinced even the most casual observer that they function somewhat differently from other people; there is not the same certainty between stimulus and response.  What they will do and how they will act under given conditions cannot be foretold with anything approaching the exactness that is possible with the normal.