 Thinkers such as Henri de Saint-Simon (1760–1825), Pierre-Simon Laplace (1749–1827) and Auguste Comte (1798–1857) believed the scientific method, the circular dependence of theory and observation, must replace metaphysics in the history of thought.Émile Durkheim (1858–1917) reformulated sociological positivism as a foundation of social research.Wilhelm Dilthey (1833–1911), in contrast, fought strenuously against the assumption that only explanations derived from science are valid.