The exposition and refutation of these pretended ethics will be the subject of the next lecture. FOOTNOTES: [187] See 2d Series, vol. ii., lect. 11 and 12; 4th Series, vol. ii., last pages of _Jacqueline Pascal_, and the _Fragments of the Cartesian Philosophy_, p. 469. [188] 1st Series, vol. iii., lectures 2 and 3, _Condillac_. [189] See the Theory of Sentiment, part i., lecture 5. LECTURE XII. THE ETHICS OF INTEREST.[190] Exposition of the doctrine of interest.--What there is of truth in this doctrine.--Its defects. 1st. It confounds liberty and desire, and thereby abolishes liberty. 2d. It cannot explain the fundamental distinction between good and evil. 3d. It cannot explain obligation and duty. 4th. Nor right. 5th. Nor the principle of merit and demerit.--Consequences of the ethics of interest: that they cannot admit a providence, and lead to despotism. The philosophy of sensation, setting out from a single fact, agreeable or painful sensation, necessarily arrives in ethics at a single principle,--interest. The whole of the system may be explained as follows: Man is sensible to pleasure and pain: he shuns the one and seeks the other. That is his first instinct, and this instinct will never abandon him. Pleasure may change so far as its object is concerned, and be diversified in a thousand ways: but whatever form it takes,--physical pleasure, intellectual pleasure, moral pleasure, it is always pleasure that man pursues. The agreeable generalized is the useful; and the greatest possible sum of pleasure, whatever it may be, no longer concentrated within such or such an instant, but distributed over a certain extent of duration, is happiness.[191] Happiness, like pleasure, is relative to him who experiences it; it is essentially personal. Ourselves, and ourselves alone we love, in loving pleasure and happiness. Interest is that which prompts us to seek in every thing our pleasure and our happiness. If happiness is the sole end of life, interest is the sole motive of all our actions. Man is only sensible to his interest, but he understands it well or ill. Much art is necessary in order to be happy. We are not ready to give ourselves up to all the pleasures that are offered on the highway of life, without examining whether these pleasures do not conceal many a pain. Present pleasure is not every thing,--it is necessary to take thought for the future; it is necessary to know how to renounce joys that may bring regret, and sacrifice pleasure to happiness, that is to say, to pleasure still, but pleasure more enduring and less intoxicating. The pleasures of the body are not the only ones,--there are other pleasures, those of mind, even those of opinion: the sage tempers them by each other.