The Solution to the Is–Ought Problem

This paper solves the is–ought problem raised by David Hume within the framework of critical rationalism. Formal impossibility proofs against is–ought inferences are correct as results within their respective systems, but they fail as general impossibility claims: they rely on conceptual fixations which, on the Quine–Duhem thesis, are revisable components of overall theoretical systems, and they immunize those fixations against criticism. Within critical rationalism, theories that protect themselves in this way from confrontation with reality are methodologically to be rejected—they say nothing about the world. Moore’s so-called “naturalistic fallacy” rests on the same basic error: “good” and “ought” are treated as monadic, goal-independent predicates and are thereby immunised against empirical criticism. This immunisation disconnects normative statements from any contact with reality and generates both the appearance of a principled gap between is and ought and the charge of a “naturalistic fallacy.” The solution reconstructs “ought” as a goal-relative operator with empirical content, without introducing additional moral premises. Ought-statements become testable hypotheses about means–end relations under specified boundary conditions. Goals form hierarchies that terminate in an ultimate goal which is not freely chosen, but is reconstructible as the teleonomically evolved goal-structure of living systems. Evolutionary theory identifies “lineage fitness” as this ultimate goal. The approach is open to criticism: its central assumptions and the norms derived from them come with explicit conditions under which they would be refuted.