Positivism \Pos"i*tiv*ism\, n. A system of philosophy originated by M. Auguste Comte, which deals only with positives. It excludes from philosophy everything but the natural phenomena or properties of knowable things, together with their invariable relations of coexistence and succession, as occurring in time and space. Such relations are denominated laws, which are to be discovered by observation, experiment, and comparison. This philosophy holds all inquiry into causes, both efficient and final, to be useless and unprofitable.

Source: Webster's Revised Unabridged Dictionary (1913)