Scientism is the position that the methods of the natural sciences are the only reliable road to knowledge, and that questions science cannot settle — about meaning, value, and God — are not real questions at all.
Scientism is less a school than a settlement reached in much modern culture: physics-envy in the social sciences, the bestseller shelf of scientific manifestos, and the reflex that a claim without a measurement is a claim without content. The word began as a criticism — Hayek's Scientism and the Counter-Revolution of Science used it against the imitation of physics by social planners — and its targets have since adopted the confidence while disputing the label.
Ultimate Reality
What exists is what science, in principle, can describe: a physical universe of matter, energy, and law, with minds, values, and societies as higher-level patterns of the same stuff. Reality is one, and its unity is methodological — every genuine phenomenon will find its place in the sciences' single account, or be retired as a confusion.
The Human Condition
The human problem is ignorance wearing costumes: superstition, ideology, and the inherited vocabularies of religion and philosophy, which mistake their metaphors for knowledge. Suffering itself is largely a technical backlog — diseases not yet cured, scarcities not yet engineered away — and the dignified response to mystery is a research program, not reverence.
Knowledge and Truth
The position's criterion is testability under the sciences' discipline: controlled experiment, mathematical formulation, replication, and peer correction. Philosophy, on this account, survives as the sciences' underlaborer or as therapy for conceptual confusion, and theology's claims fail the entrance requirement entirely — not false, in the stricter versions, but not candidates for truth.
Right and Wrong
Ethics, for scientism, must be naturalized: well-being and suffering are facts about nervous systems, so morality is an engineering discipline of consequences awaiting its science. Sam Harris's The Moral Landscape states the claim in its purest form. What the position cannot permit is a value that floats free of the measurable world — a command with no fact beneath it is only a noise with authority's accent.
Human Destiny
Destiny is progress without a terminus: the indefinite extension of knowledge and power, the colonization of ignorance frontier by frontier. There is no final state and no judge; the species' story is its own to continue or to end, and meaning is not found in the cosmos but manufactured, honestly, by the beings who need it.
The Conversation
Scientism asks philosophy and theology to name one item of knowledge either has produced by its own methods in a century. Its critics — scientists prominently among them — return the question in a sharper form: by what experiment is the claim 'only experimental claims are knowledge' itself established? The position's strength is the sciences' record; its weakness is that the record does not include the position.