has the three problems of (1) giving an account of the means of knowledge, (2) applying these means to our will, (3) applying them to the study of external objects. To these correspond three groups of sciences: (1) ideology, grammar, logic; (2) political economy, morals, politics; (3) physics, geometry, arithmetic.

Ideology. Ideology is the "first philosophy," upon which all other sciences depend for their foundation and method. All ideas and faculties originate in sensation; to think is to feel (penser, c'est sentir). The immediate objects of the faculty of thinking or feeling may be termed "sensations," "sentiments," "ideas," "perceptions." These are of four classes,- 66 sensations proper," ," "memories," "relations between sensations," "desires." Four corresponding faculties are: sensibility, properly so called, memory, judgment, will. Sensibility is the property of our nature by virtue of which we receive impressions of various sorts and have consciousness. Our "external" sensations are caused by the action of objects upon the extremities of the nerves: "internal" sensations by the action of the nerves in the interior of the body resulting from the functioning of organs or lesions of different parts of the body, etc. Memory depends on certain permanent conditions of the brain. Judgment is directly involved in the connecting, in a feeling of agreement, of sensations. Desire and will are respectively passive and active conditions of the same form of thinking faculty. All acts of the thinking faculty, will included, are subject to the law of necessity. Our knowledge of external objects as such comes through the feeling of resistance acquired through voluntary movement. Ideology is a part of zoölogy (i. e., in later terminology, psychology is a part of biology). De Tracy's ideology is a combination of the physiological psychology of Cabanis with the "introspective" psychology of Condillac, the latter element predominating.

Morals. Man, as having desires, has a capacity for suffering and enjoyment, has needs, rights, duties. His rights

are determined by his needs, his duties by his power of satisfying these. The fundamental principle of morals is that our "rights are always without limit, our duties are always only the general duty of satisfying our needs: every one has the right to do what he pleases and can; there is neither justice nor injustice."

Politics. The true government is one of pure representation under one or more leaders, a government sprung from and founded on the general will, having for its principle reason, its means liberty, its effects happiness a government in which the rulers are servants, and punishment is simply for the prevention of wrong. Here we have in a nutshell the "philosophy" of the moving spirit of the French Revolution.

Result. De Tracy has been called the "logician or metaphysician" of the "sensualistic school."

§ 86.

Claude Adrien Helvétius1 (1715-1771).- Helvétius, who was the son of the court-physician at Paris, and educated at the Collège of Louis-le-Grand, had, it would seem, neither externally nor internally very favorable conditions given him for the attainment of philosophic wisdom. He had influential friends, was wealthy, vain of his person, without taste for really scientific pursuits, ambitious to shine in polite society, was, in short, a spoiled favorite of earthly fortune. He held a lucrative political office for a number of years, and feasted his friends frequently after he retired from it. The publication of Condillac's "Traité des Sensations" excited his intellectual vanity to attempt the production of a philosophical work, the result of his attempt being the (once) famous "De l'Esprit." He died. of an attack of gout. He left behind a name for kindliness and for liberality in giving. In his youth he was fond of reading Locke.

1 Noack; Martineau, "Types of Ethical Theory," vol. ii.

Works. Besides the "De l'Esprit" (1758), which is his best work, he composed numerous other works, of which we may mention here "De l'Homme; de ses

Facultés intellectuelles et de son Éducation (1772),

which is a new version of the earlier work, — and "Les Progrès de la Raison dans le Recherche du Vrai" (1775). There were published in various languages, fifty editions of the "De l'Esprit " in a short time.

Philosophy. The opinions of Helvétius were very largely borrowed from writers of the empirico-sensualistic school. In man, says Helvétius, all is the result of bodily organization, and is to be explained by corporeal sensibility. The law of man's nature is to seek pleasure and avoid pain. By this law the law of interest he acquires ideas, or the impressions of relations, and the power of understanding; by this law also are his actions determined: man is a machine set in motion and kept running by corporeal sensibility. The passions of man, which have their origin purely in the impulse to seek pleasure and avoid pain, are of two sorts,- those depending immediately on the bodily sensations, and those depending on ideal, that is, artistic and social, sensations. Both sorts centre in selflove, by which even the most disinterested actions are explainable. "If a man does good to his fellows, if he sacrifices himself for his father, his son, or his country, it is because he finds in doing that action, in imposing a sacrifice upon himself, a pleasure greater than the sufferings which may follow it. An action which, besides procuring pleasure for ourselves, also benefits others, receives the name of virtue; but all virtue has for its final purpose the satisfying of self-interest." The problem of morals and legislation is to combine the interest of the whole with that of the individual. There is and can be no conflict between virtue and justice, on the one hand, and interest, on the other. Rather are the passions necessary to the highest virtue. The virtue of him who is incapable of passion is a passive virtue, the virtue of indolence. We

require passion to prevent us from gravitating continually towards indolence and inactivity; hence the passions must be encouraged, strengthened. To this end it is necessary to gratify them, to excite them with promised rewards and threatened punishment, to elaborate them by means of education. Without them there is nothing good or beautiful or great among men. The unhappiness of men is merely the consequence of an unenlightened self-love. Let men be educated to a full consciousness of their moving principle. All men are by nature equal in capacity of self-enjoyment, since all have the same natural power of sensibility; the differences among them are differences of education. Legislators should exercise the power they have to mould by education the characters and manners of the people as they please. They should employ this power for the increase of the happiness (the greatest possible physical pleasure) of man. - Helvétius has exercised an influence, through Bentham, upon Nineteenth Century Utilitarianism.

$ 87.

Denis Diderot (1713-1784). — Diderot was educated at a Jesuit school at Langres (his birthplace) and at the Collège d'Harcourt in Paris. Refusing to adopt, in accordance with the wish of his father, the profession of law, he chose that of letters, in which after many years of hard labor and privation he acquired great eminence, particularly as chief editor of, and contributor towards, the great French "Encyclopédie." Though not a very systematic thinker, he is regarded as one of the most original and fertile minds of France of the eighteenth century.

Works. Diderot's standpoint twice changed: he was a "theist," a 66 deist," and an "atheist (or rather naturalistic pantheist) in succession. His "Principes de la Philosophie Morale, ou Essai sur la Vérité et sur la Vertu" (1745) a free rendering of Shaftesbury's "Inquiry Concerning Virtue and Merit " was written by him as a "theist." In

his "Pensées Philosophiques" (1746), " Promenade d'un Sceptique" (1747), "Lettre sur les Aveugles' (1749), "Lettres sur les Sourds et Muets" (1751), and in his articles for the "Encyclopédie, ou Dictionnaire Raisonné des Sciences, des Arts, et des Métiers" (1751-1757), he is generally deist. (The "Encyclopédie " was a sort of mouthpiece of the deistic and materialistic thinkers in France in the mid

dle of last century.) His atheistic views are expressed in his "Pensées sur l'Interprétation de la Nature" (1754), "Entretien entre d'Alembert et Diderot" (1769), “Le Rêve d'Alembert" (1769), — a sequel to the "Entretien," "Sur la Matière et le Mouvement" (1770).

Philosophy. — In his first period Diderot regards orthodox theism as the only metaphysical doctrine favorable to virtue, and deism as shallow. In his second, or as a deist, he thinks that even atheism is preferable to superstition, and that metaphysic, in the ordinary sense, is as nothing compared with common-sense, that the only weapons of warfare against atheism are the Newtonian physics, that natural religion is the only religion superior to all cavil or objection. In his third period Diderot maintains the view that the first principle of things is matter endowed with a psychic force, or life. Everywhere there is sensibility and activity, though in the lower and lowest grades of being these are, as it were, imprisoned. "Body is, according to some philosophers, in itself without action and without force. This is a monstrous error, contrary to all good physics, to all good chemistry. In itself, by the nature of its essential qualities, whether it be considered in molecules or in masses, it is full of activity and force." This new view takes with Diderot, first, the shape of a (quasi-Leibnitzian) dynamic atomism, and afterwards of a pure monism, since he denies all real independent existence of individuals, and asserts that only of one individual,— the All. Man is a part of nature; the soul is not separate from the body, psychology is merely physiology of the nerves. In the properties and conditions of our sense