David Warren clarifies the meaning of “scientism”:
[T]he label “scientism” applies to all who imagine that natural science, and the methods of natural science, take precedence before, and have authority over, every other field of human reasoning and perception. To a truly “scientistic” worldview, not only philosophy and theology, but psychology, art, culture, law, and general morality, are answerable not to their own terms of reference, but to some authority in a lab coat who has bred clouds of deformed fruitflies, and killed a lot of mice.
The philosophical position corresponding to scientism is called “Positivism,”and was systematized by Auguste Comte (the man who coined the term “sociology”), in the 19th century. He was building upon the revolutionary heritage of the French Enlightenment; but he was also expressing the God-like aspirations of parlour atheism in the Victorian age — its “determinism,” or faith that once everything is known, everything can be predicted. Lamarckianism, Darwinism, Marxism, Freudianism, and Phrenology were, to my mind, five other expressions of this naive determinism, that belong today in a Museum of Failed Victorian Ideas. . . .
In the older view, that never needed to be superseded, science was not put at the apex of human life, and sciencers, scientiates, sciencists, scientmen, or “scientists” as they were finally called, were not presented to the world as high priests, privy to some secret, mystical code.