Scientism has two meanings. One refers to the (almost religious) belief that science may eventually understand and solve all natural and human problems. This kind of scientism has also been called “scientific fundamentalism.” Wikipedia gives a good outline of this approach:
Scientism is belief in the universal applicability of the scientific method and approach, and the view that empirical science constitutes the most “authoritative” worldview or the most valuable part of human learning – to the exclusion of other viewpoints. Accordingly, philosopher 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.”¹
The second meaning refers to the partial and/or deceptive use of methods generally recognized as scientific.
Put simply, some people actively deceive or try to appear scientific for personal, economic or political gain. For examples of this see Betrayers of the Truth: Fraud and Deceit in the Hall of Science by W. Broad and N. Wade (1982). More recent examples can be found here:
Related to the second meaning, a specious argument may be given a scientific gloss to make it seem legitimate. We find this in so many TV ads where professional actors wear white lab coats, trying to look like authoritative scientists or medical professionals while selling products ranging from automobiles to toothpaste.
Also, the representation of statistics may be disproportional to actual results. Sometimes we find bloated or extended bar graphs that make results look more significant than they really are—another common advertising trick that falls under this kind of scientism.
Because the entire definition of science is problematic, one could say that the idea of scientism, itself, is also fraught with difficulty. Science is a human enterprise. And in my opinion it’s often a fine line between science and scientism. Or maybe a gray and blurry one.