Philosophy is dead,’ Stephen Hawking once declared, because it ‘has not kept up with modern developments in science, particularly physics.’ It is scientists, not philosophers, who are now ‘the bearers of the torch of discovery in our quest for knowledge’. The response from some philosophers was to accuse Hawking of ‘scientism’. The charge of ‘scientism’ is meant to convey disapproval of anyone who values scientific disciplines, such as physics, over non-scientific disciplines, such as philosophy. The philosopher Tom Sorell writes that scientism is ‘a matter of putting too high a value on science in comparison with other branches of learning or culture’. But what’s wrong with putting a higher value on science compared with other academic disciplines? What is so bad about scientism? If physics is in fact a better torch in the quest for knowledge than philosophy, as Hawking claimed, then perhaps it should be valued over philosophy and other non-scientific fields of enquiry.

Before we can address these questions, however, we need to get our definitions straight. For, much like other philosophical -isms, ‘scientism’ means different things to different philosophers. Now, the question of whether science is the only way of knowing about reality, or at least better than non-scientific ways of knowing, is an epistemological question. Construed as an epistemological thesis, then, scientism can be broadly understood as either the view that scientific knowledge is the only form of knowledge we have, or the view that scientific knowledge is the best form of knowledge we have. But scientism comes in other varieties as well, including methodological and metaphysical ones. As a methodological thesis, scientism is either the view that scientific methods are the only ways of knowing about reality we have, or the view that scientific methods are the best ways of knowing about reality we have. And, construed as a metaphysical thesis, scientism is either the view that science is our only guide to what exists, or the view that science is our best guide to what exists.