While doing some quick research for a friend, I ran across an excerpt from the following work:
The Psychology of Profanity. By G. T. W. Patrick.
The psychology of profanity, when finally written, will throw considerable light upon two unsolved but much-discussed problems: first, the origin of language, and second, the relation between emotion and expression... Words and phrases used in profane swearing may be divided roughly into seven classes:
1. Names of deities, angels, and devils.
2. Names connected with the sacred matters of religion.
3. Names of saints, holy persons, and biblical characters.
4. Names of sacred places.
5. Words relating to the future life.
6. Vulgar words.
7. Expletives.
The history of profanity is closely connected with the history of religion, since profanity prevailed at those times and among those people where great sacredness attached to the names of the gods, or to matters of religion. In England, for instance, in the thirteenth and fourteenth centuries, after the monkish teaching had implanted a vivid consciousness of the suprasanctity of the body of Christ, and of every scene connected with His death, there burst upon the country a wave of imprecation in which profane use was made of the body and members and wounds of Christ, and of many things connected with His sufferings. Fossil remains of these oaths have come down to us in such expressions as 'zounds,' 's'death,' 'bodikins,' 'odsbodikins,' etc. The significance of this historical circumstance will be seen when we discover that the psychological value of an oath depends upon the force of the 'shock' which it is capable of giving. The occasion of profanity in general is a situation in which there is a high degree of emotion, usually of the aggressive type, accompanied by a certain feeling of helplessness. In cases of great fear, where action is impossible, as in impending shipwreck, men pray; in great anger, unless they can act, they swear. The subjective effects of profanity are characteristic and peculiar. The most striking effect is that of a pleasant feeling of relief from a painful stress. It has a pacifying or purifying effect... profanity is ancient and deep-seated, and probably one of the oldest forms of language.
In animal life, anger is the psychical accompaniment of a failure to coördinate the usual sensory and motor elements connected with combat. Any modifications of the usual reactions of combat of such a character as to induce in the opponent reactions of flight, will be useful and therefore preserved. Terrifying forms of phonation, such as the growl or the roar, are of this characacter[sic]. As vocal language develops, this vocalization will always select the most terrifying, the most 'shocking' words. All the words actually used in profanity are found to possess this common quality. Profanity is to be understood as originally not an expression of emotion, but as a life-serving form of activity. It does not generate emotion. Indirectly it allays it.
You can find more by going here.
(I "bolded" text for added emphasis -- Chris)
So I'm wondering...should profanity (or certain types of profanity) be allowed or perhaps encouraged?