The third consideration is the degree to which we apprehend that endless chain of causation inevitably demanded by reason, in which each phenomenon comprehended, and therefore man's every action, must have its definite place as a result of what has gone before and as a cause of what will follow.
The better we are acquainted with the physiological, psychological, and historical laws deduced by observation and by which man is controlled, and the more correctly we perceive the physiological, psychological, and historical causes of the action, and the simpler the action we are observing and the less complex the character and mind of the man in question, the more subject to inevitability and the less free do our actions and those of others appear.
When we do not at all understand the cause of an action, whether a crime, a good action, or even one that is simply nonmoral, we ascribe a greater amount of freedom to it. In the case of a crime we most urgently demand the punishment for such an act; in the case of a virtuous act we rate its merit most highly. In an indifferent case we recognize in it more individuality, originality, and independence. But if even one of the innumerable causes of the act is known to us we recognize a certain element of necessity and are less insistent on punishment for the crime, or the acknowledgment of the merit of the virtuous act, or the freedom of the apparently original action. That a criminal was reared among male factors mitigates his fault in our eyes. The self-sacrifice of a father or mother, or self-sacrifice with the possibility of a reward, is more comprehensible than gratuitous self-sacrifice, and therefore seems less deserving of sympathy and less the result of free will. The founder of a sect or party, or an inventor, impresses us less when we know how or by what the way was prepared for his activity. If we have a large range of examples, if our observation is constantly directed to seeking the correlation of cause and effect in people's actions, their actions appear to us more under compulsion and less free the more correctly we connect the effects with the causes. If we examined simple actions and had a vast number of such actions under observation, our conception of their inevitability would be still greater. The dishonest conduct of the son of a dishonest father, the misconduct of a woman who had fallen into bad company, a drunkard's relapse into drunkenness, and so on are actions that seem to us less free the better we understand their cause. If the man whose actions we are considering is on a very low stage of mental development, like a child, a madman, or a simpleton — then, knowing the causes of the act and the simplicity of the character and intelligence in question, we see so large an element of necessity and so little free will that as soon as we know the cause prompting the action we can foretell the result.
On these three considerations alone is based the conception of irresponsibility for crimes and the extenuating circumstances admitted by all legislative codes. The responsibility appears greater or less according to our greater or lesser knowledge of the circumstances in which the man was placed whose action is being judged, and according to the greater or lesser interval of time between the commission of the action and its investigation, and according to the greater or lesser understanding of the causes that led to the action.