concept
Phillips Curve
The empirical relationship — observed by A. W. Phillips in UK data, 1861–1957 — between unemployment and the rate of change of money wages. Reinterpreted in the 1960s as a relationship between unemployment and price inflation, and read variously as a stable policy menu, a short-run-only trade-off, or no causal relationship at all.
Stub entry.
The Phillips Curve begins as an empirical observation — Phillips (1958) noted an inverse relation between unemployment and money-wage growth in long-run UK data. Samuelson and Solow (1960) reinterpreted it as an inflation-unemployment trade-off and a guide for policy. Phelps (1967) and Friedman (1968) argued that any such trade-off would shift as expectations adjusted, leaving a vertical long-run curve at the natural rate of unemployment.
Stagflation in the 1970s appeared to confirm the Phelps-Friedman view; the curve was reformulated, then incorporated into New Keynesian models with rational expectations. Post-Keynesian accounts question whether the curve identifies a stable causal relationship at all, locating wage and price dynamics in distributional conflict rather than in unemployment-driven slack.
The concept is contested at every level — definition, mechanism, time-frame, policy implication — and each tradition’s reading of it is a small map of the tradition itself.