 Comte’s most important works are (1) the Course on Positive Philosophy (1830–1842, six volumes, translated and condensed by Harriet Martineau as The Positive Philosophy of Auguste Comte); (2) the System of Positive Polity, or Treatise on Sociology, Instituting the Religion of Humanity, (1851–1854, four volumes); and (3) the Early Writings (1820–1829), where one can see the influence of Saint-Simon, for whom Comte served as secretary from 1817 to 1824. The Early Writings are still the best introduction to Comte’s thought. In the Course, Comte said, science was transformed into philosophy; in the System, philosophy was transformed into religion. The second transformation met with strong opposition; as a result, it has become customary to distinguish, with Mill, between a “good Comte” (the author of the Course) and a “bad Comte” (the author of the System). Today’s common conception of positivism corresponds mainly to what can be found in the Course.