Is it not a rule of prudence not to listen to, without always disdaining them, the inspirations--often capricious--of the heart? Governed by reason, sentiment becomes to it an admirable support. But, delivered up to itself, in a little while it degenerates into passion, and passion is fantastic, excessive, unjust; it gives to the soul spring and energy, but generally troubles and perverts it. It is even not very far from egoism, and it usually terminates in that, wholly generous as it is or seems to be in the beginning. Unless we always keep in sight the good and the inflexible obligation that is attached to it, unless we always keep in sight this fixed and immutable point, the soul knows not where to betake itself on that moving ground that is called sensibility; it floats from sentiment to passion, from generosity to selfishness, ascending one day to the pitch of enthusiasm, and the next day descending to all the miseries of personality. Thus the ethics of sentiment, although superior to those of interest, are not less insufficient: 1st. They give as the foundation of the idea of the good what is founded on this same idea; 2d. The rule that they propose is too mobile to be universally obligatory.[205] There is another system of which I will also say, as of the preceding, that it is not false, but incomplete and insufficient. The partisans of the ethics of utility and happiness have tried to save their principle by generalizing it. According to them, the good can be nothing but happiness; but egoism is wrong in understanding by that the happiness of the individual; we must understand by it the general happiness. Let us establish, in the first place, that the new principle is entirely opposed to that of personal interest, for, according to circumstances, it may demand, not only a passing sacrifice, but an irreparable sacrifice, that of life. Now, the wisest calculations of personal interest cannot go thus far. And, notwithstanding, this principle is far from containing true ethics and the whole of ethics.