Crime, strictly speaking, is only such conduct or acts as are forbidden by the law and for which penalties are prescribed. The classification of the act does not necessarily have relation to moral conduct. This cannot be fixed by any exact standard. There is no straight clear line between the good and bad, the right and wrong. The general ways of determining good and bad conduct are of little value. The line between the two is always uncertain and shifting. And, in the last analysis, good or bad conduct rests upon the "folk-ways," the habits, beliefs and customs of a community. While this is the real basis of judging conduct, it is always changing, and from the nature of things, if it could be made stable, it would mean that society was stratified and all hope of improvement dead.
Neither the purpose nor the effect of punishment has ever been definitely agreed upon, even by its most strenuous advocates. So long as punishment persists it will be a subject of discussion and dispute. No doubt the idea of punishment originated in the feeling of resentment and hatred and vengeance that, to some extent at least, is incident to life. The dog is hit with a stick and turns and bites the stick. Animals repel attack and fight their enemies to death. The primitive man vented his hatred and vengeance on things animate and inanimate. In the tribes no injury was satisfied until some member of the offending tribe was killed. In more recent times family feuds have followed down the generations and were not forgotten until the last member of a family was destroyed. Biologically, anger and hatred follow fear and injury, and punishment follows these in turn. Individuals, communities and whole peoples hate and swear vengeance for an injury, real or fancied. Punishments, even to the extent of death, are inflicted where there can be no possible object except revenge. Whether the victim is weak or strong, old or young, sane or insane, makes no difference; men and societies react to injury exactly as animals react.
That vengeance is the moving purpose of punishment is abundantly shown by the religious teachings that shape the ethical ideas of the Western world. The Old Testament abounds in the justification of vengeance. A few quotations amply show the Biblical approval of this doctrine: