Scientism is a term generally used to describe the cosmetic application of science in unwarranted situations not covered by the scientific method.

In philosophy of science, the term "scientism" frequently implies a critique of the more extreme expressions of logical positivism and has been used by social scientists such as Friedrich Hayek, philosophers of science such as Karl Popper, and philosophers such as Hilary Putnam and Tzvetan Todorov to describe (for example) the dogmatic endorsement of scientific methodology and the reduction of all knowledge to only that which is measured or confirmatory.

More generally, scientism is often interpreted as science applied "in excess". The term scientism can apply in either of two senses:

1.To indicate the improper usage of science or scientific claims. This usage applies equally in contexts where science might not apply, such as when the topic is perceived as beyond the scope of scientific inquiry, and in contexts where there is insufficient empirical evidence to justify a scientific conclusion. It includes an excessive deference to claims made by scientists or an uncritical eagerness to accept any result described as scientific. This can be a counterargument to appeals to scientific authority. It can also address the attempt to apply "hard science" methodology and claims of certainty to the social sciences, which Friedrich Hayek described in The Counter-Revolution of Science (1952) as being impossible, because that methodology involves attempting to eliminate the "human factor", while social sciences (including his own field of economics) center almost purely on human action.
2.To refer to "the belief that the methods of natural science, or the categories and things recognized in natural science, form the only proper elements in any philosophical or other inquiry",or that "science, and only science, describes the world as it is in itself, independent of perspective" with a concomitant "elimination of the psychological [and spiritual] dimensions of experience".Tom Sorell provides this definition of scientism: "Scientism is a matter of putting too high a value on natural science in comparison with other branches of learning or culture."Philosophers such as Alexander Rosenberg have also appropriated "scientism" as a name for the view that science is the only reliable source of knowledge