Self-love or interest, says Helvetius, is the lever of all our mental activities. Even that activity which is purely intellectual, our instinct towards knowledge, our forming of ideas, rests upon this. Since now all self-love refers essentially only to bodily pleasure, it follows that every mental occurrence within us has its peculiar source only in the striving after this pleasure; but in saying this, we have only affirmed where the principle of all morality is to be sought. It is an absurdity to require a man to do the good simply for its own sake. This is just as impracticable as that he should do the evil simply for the sake of the evil. Hence if morality would not be wholly fruitless, it must return to its empirical basis, and venture to adopt the true principle of all acting, viz., sensuous pleasure and pain, or, in other words, selfishness as an actual moral principle. Hence, as a correct legislation is that which secures obedience to its laws through reward and punishment, _i. e._ through selfishness, so will a correct system of morals be that which derives the duties of men from self-love, which shows that that which is forbidden is something which is followed by disagreeable consequences. A system of ethics which does not involve the self-interest of men, or which wars against this, necessarily remains fruitless.
THE FRENCH CLEARING UP (_Aufklaerung_) AND MATERIALISM.
1. It has already been remarked (§ XXX.) that the carrying out of empiricism to its extremes, as was attempted in France, was most intimately connected with the general condition of the French people and state, in the period before the revolution. The contradictory element in the character of the Middle Ages, the external and dualistic relation to the spiritual world, had developed itself in Catholic France till it had corrupted and destroyed every condition. Morality, mainly through the influence of a licentious court, had become wholly corrupted; the state had sunk to an unbridled despotism, and the church to a hierarchy as hypocritical as it was powerful. Thus, as every intellectual edifice was threatened with ruin, nature, as matter without intellect, as the object of sensation and desire, alone remained. Yet it is not the materialistic extreme which constitutes the peculiar character and tendency of the period now before us. The common character of the philosophers of the eighteenth century is rather, and most prominently, the opposition against every ruling restraint, and perversion in morals, religion, and the state. Their criticism and polemics, which were much more ingenious and eloquent than strictly scientific, were directed against the whole realm of traditional and given and positive notions. They sought to show the contradiction between the existing elements in the state and the church, and the incontrovertible demands of the reason. They sought to overthrow in the faith of the world every fixed opinion which had not been established in the eye of reason, and to give the thinking man the full consciousness of his pure freedom. In order that we may correctly estimate the merit of these men, we must bring before us the French world of that age against which their attacks were directed; the dissoluteness of a pitiful court, the slavish obedience exacted by a corrupt priesthood, a church sunken into decay yet seeking worldly honor, a state constitution, a condition of rights and of society, which must be profoundly revolting to every thinking man and every moral feeling. It is the immortal merit of these men that they gave over to scorn and hatred the abjectness and hypocrisy which then reigned; that they brought the minds of men to look with indifference upon the idols of the world, and awakened within them a consciousness of their own autonomy.