This chief good, or this highest happiness, being the end of moral action, one point about it is at once evident.  Its value is of course recognised by those who practise morality, or who enunciate moral systems.  Virtuous men are virtuous because the end gained by virtue is an end that they desire to gain.  But this is not enough; it is not enough that to men who are already seeking the good the good should appear in all its full attractiveness.  It must be capable of being made attractive for those who do not know it, and who have never sought it, but who have, on the contrary, always turned away from everything that is supposed to lead to it.  It must be able, in other words, not only to satisfy the virtuous of the wisdom of their virtue, it must be able to convince the vicious of the folly of their vice.  Vice is only bad in the eye of the positive moralist because of the precious something that we are at the present moment losing by it.  He can only convince us of our error by giving us some picture of our loss.  And he must be able to do this, if his system is worth anything; and in promulgating his system he professes that he can do it.  The physician’s work is to heal the sick; his skill must not end in explaining his own health.  It is clear that if a morality is incapable of being preached, it is useless to say that it is worthy of being practised.  The statement will be meaningless, except to those for whom it is superfluous.  It is therefore essential to the moral end that in some way or other it be generally presentable, so that its excellence shall appeal to some common sense in man.  And again, be it observed, that we are demanding no mathematical accuracy.  We demand only that the presentation shall be accurate enough to let us recognise its corresponding fact in life.

Now what is a code of morals, and why has the world any need of one?  A code of morals is a number of restraining orders; it rigorously bids us walk in certain paths.  But why?  What is the use of bidding us?  Because there are a number of other paths that we are naturally inclined to walk in.  The right path is right because it leads to the highest kind of happiness; the wrong paths are wrong because they lead to lower kinds of happiness.  But when men choose vice instead of virtue, what is happening?  They are considering the lower or the lesser happiness better than the greater or the higher.  It is this mistake that is the essence and cause of immorality; it is this mistake that mankind is ever inclined to make, and it is only because of this inclination that any moral system is of any general value.