consist in them (thought is a function of the brain), and makes psychology, as the physics of the nerves, a part of physiology. The denial of immortality and the divine origin of the world is, however, by no means to follow from materialism. Priestley not only combated the atheism of Holbach, but also entered the deistic ranks with works of his own on Natural Religion and the Corruptions of Christianity. [Footnote 1: Hartley, _Observations on Man, his Frame, his Duties, his Expectations_. 1749.] [Footnote 2: Priestley, _Hartley's Theory of the Human Mind on the Principles of the Association of Ideas_, 1775; _Disquisitions relating to Matter and Spirit_, 1777; _The Doctrine of Philosophical Necessity_, 1777; _Free Discussions of the Doctrines of Materialism_, 1778 (against Richard Price's _Letters on Materialism and Philosophical Necessity_). Cf. on both Schoenlank's dissertation, _Hartley und Priestley, die Begründer des Assoziationismus in England_, 1882.] As early as in Hartley[1] the principle, which is so important for ethics, appears that things and actions (_e.g._, promotion of the good of others) which at first are sought and done because they are means to our own enjoyment, in time come to have a direct worth of their own, apart from the original egoistic end. James Mill (1829) has repeated this thought in later times. As fame becomes an immediate object of desire to the ambitious man, and gold to the miser, so, through association, the impulse toward that which will secure approval may be transformed into the endeavor after that which deserves approval. [Footnote 1: Cf. Jodl, _Geschichte der Ethik_, vol. i. p. 197 _seq_.] Among later representatives of the Associational school we may mention Erasmus Darwin _(Zoönomia, or the Laws of Organic Life_, 1794-96). %2. Deism%. As Bacon and Descartes had freed natural science, Hobbes, the state, and Grotius, law from the authority of the Church and had placed them on an independent basis, _i.e._, the basis of nature and reason, so deism[1] seeks to free religion from Church dogma and blind historical faith, and to deduce it from natural knowledge. In so far as deism finds both the source and the test of true religion in reason, it is rationalism; in so far as it appeals from the supernatural light of revelation and inspiration to the natural light of reason, it is naturalism; in so far as revelation and its records are not only not allowed to restrict rational criticism, but are made the chief object of criticism, its adherents are freethinkers. [Footnote 1: Cf. Lechler's _Geschichte des Englischen Deismus_, 1841, which is rigorously drawn from the sources. [Hunt, _History of Religious Thought in England_, 1871-73 [1884]; Leslie Stephen, _History of English Thought in the Eighteenth Century_, 1876 [1880]; Cairns, _Unbelief in the Eighteenth Century_, 1881.]]