§3. In the last section we have spoken chiefly of the appetites for food and drink. It is, however, in the case of the appetite of sex that the regulation morally prescribed most clearly and definitely transcends that of mere prudence: which is indicated by the special notion of Purity or Chastity.
At first sight it may perhaps appear that the regulation of the sexual appetite prescribed by the received moral code merely confines its indulgence within the limits of the union sanctioned by law: only that here, as the natural impulse is peculiarly powerful and easily excited, it is especially necessary to prohibit any acts, internal as well as external, that tend even indirectly to the transgression of these limits. And this is to a great extent true: still on reflection it will appear, I think, that our common notion of purity implies a standard independent of law; for, first, conformity to this does not necessarily secure purity: and secondly, all illegitimate sexual intercourse is not thought to be impure, and it is only by inadvertence that the two notions are sometimes confounded. But it is not very clear what this standard is. For when we interrogate the moral consciousness of mankind, we seem to find two views, a stricter and a laxer, analogous to the two interpretations of Temperance last noticed. It is agreed that the sexual appetite ought never to be indulged for the sake of the sensual gratification merely, but as a means to some higher end: but some say that the propagation of the species is the only legitimate, as it is obviously the primary natural, end: while others regard the development of mutual affection in a union designed to be permanent as an end perfectly admissible and right. I need not point out that the practical difference between the two views is considerable; so that this question is one which it is necessary to raise and decide. But it may be observed that any attempt to lay down minute and detailed rules on this subject seems to be condemned by Common Sense as tending to defeat the end of purity; as such minuteness of moral legislation invites men in general to exercise their thoughts on this subject to an extent which is practically dangerous.
I ought to point out that the Virtue of Purity is certainly not merely self-regarding, and is therefore properly out of place in this chapter: but the convenience of discussing it along with Temperance has led me to take it out of its natural order. Some, however, would go further, and say that it ought to be treated as a distinctly social virtue: for the propagation and rearing of children is one of the most important of social interests: and they would maintain that Purity merely connotes a sentiment protective of these important functions, supporting the rules which we consider necessary to secure their proper performance. But it seems clear that, though Common Sense undoubtedly recognises this tendency of the sentiment of Purity to maintain the best possible provision for the continuance of the human race, it still does not regard that as the fundamental point in the definition of this rule of duty, and the sole criterion in deciding whether acts do or do not violate the rule.
There seem to be no similar special questions with respect to most other desires. We recognise, no doubt, a general duty of self-control: but this is merely as a means to the end of acting rationally (whatever our interpretation of rational action may be); it only prescribes that we should yield to no impulse which prompts us to act in antagonism to ends or rules deliberately accepted. Further, there is a certain tendency among moral persons to the ascetic opinion that the gratification of merely sensual impulse is in itself somewhat objectionable: but this view does not seem to be taken by Common Sense in particular cases;---we do not (e.g.) commonly condemn the most intense enjoyment of muscular exercise, or warmth, or bathing. The only other case, besides that of the appetites above discussed, in which the Common Sense of our age and country seems to regard as right or admirable the repression of natural impulses, beyond what Prudence and Benevolence would dictate, is that of the promptings of pain and fear. An important instance of this is to be found in the before-mentioned rule prohibiting suicide absolutely, even in face of the strongest probability that the rest of a man's life will be both miserable and burdensome to others. But in other cases also praise is apparently bestowed on endurance of pain and danger, beyond what is conducive to happiness; as we shall have occasion to observe in the next chapter.