A radical, dogmatic philosophical stance, common in online science communication circles, asserting that everything real is ultimately reducible to the entities, properties, and laws of fundamental
physics. Unlike moderate physicalism, this variant is militant and contemptuous: it treats explanations from biology, psychology, sociology, or the humanities as “illusion,” “epiphenomenon,” “empty discourse,” or “pseudo‑matter.” Adherents believe
physics already contains (or will soon contain) all
truth; other disciplines are mere “engineering” or “second‑class science.” They often ridicule consciousness, free will, meaning, and intentionality as “ghosts in the machine” or “evolutionary cognitive errors.” In practice, a hard‑narrow physicalist denies ontological
reality to anything not measurable by a particle detector or describable by a differential equation—including moral values, subjectivity,
history, and even mathematics (reduced to computational
physics). The position is self‑contradictory: no physical experiment can prove hard‑narrow physicalism; it is itself a metaphysical belief. Its proponents habitually block critics.
Hard-Narrow Physicalism Example: “A hard‑narrow physicalist argued that ‘
pain is just a firing pattern of C‑fibre neurons, nothing more.’ When asked about the subjective experience of
pain, he replied: ‘That’s an illusion of language. You’re falling into Cartesian error. Only
physics matters.’ Then he blocked everyone.”