reductionists

Reductionists are proponents of reductionism, the view that phenomena at one level of organization can be explained in terms of more fundamental, lower‑level processes. In philosophy of science, reductionism is usually divided into methodological reductionism, which argues that theories should be formulated in terms of basic entities when possible, and ontological (strong) reductionism, which claims that higher‑level entities literally do not exist independently and are reducible to lower‑level constituents. Weak reductionism allows that higher‑level descriptions may be useful but should ultimately be grounded in lower‑level explanations.

Historically, reductionism has driven scientific ambitions to unify explanations, such as the ambition to reduce biology to chemistry and physics. In the philosophy of science, Ernst Nagel’s account of theoretical reduction and the notion of bridging laws shaped debates about when a reduction is legitimate. In the philosophy of mind, some thinkers, notably the Churchlands, argue for neuroreduction—the identification of mental states with brain states—though this position remains controversial and incomplete in practice.

Critics point to emergent properties, multiple realizability, and causal exclusion as challenges to reductionism. They contend that some phenomena exhibit features not predictable from or reducible to lower-level laws, or that lower‑level explanations cannot capture the causal structure of higher‑level domains. Today, reductionist ideas persist in many sciences, while many researchers adopt a pluralistic or pragmatically reductionist stance, recognizing both the explanatory gains of reduction and the explanatory demands of higher-level theories.