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Vallicella: Rosenberg's Definition of Scientism and the Problem of Defining 'Scientism' --

So I say, nontrivially,

2. Scientism is the view that the only genuine knowledge is natural-scientific knowledge.

Among the natural sciences we have, in first place, physics. And so a really hard-assed 'scientisticist' (to coin a word as barbarous as what it names) might that hold that

3. Scientism is the view that the only genuine knowledge is physics and whatever can be reduced to physics.

The word you're looking for is 'scientiste' (in the manner of Miss Piggy, the Artiste), which word is silent on whether the person so denoted is employed as a scientist, or even understands, much less cares, what 'science' is and is not, can and cannot tell us.

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