When Physicists Say “Prediction”: 1 What We Think Prediction Is

Prediction carries an intuitive weight: it is the claim that a theory can anticipate the future, that events will unfold in accordance with some general principle or law. We feel confident that when a scientist predicts, she stakes something on the world — a temporal, experiential commitment. The kettle will boil, the comet will appear, the particle will arrive in the detector.

This sense is older than quantum mechanics or contemporary physics. It is embedded in classical scientific practice: Newton calculated the return of Halley’s Comet centuries before observation; Maxwell anticipated the propagation of electromagnetic waves; thermometers foretold the frost. Prediction, in this sense, is a bridge from theory to phenomenon — a test of intelligibility and engagement with experience.

The bridge is not merely functional; it is normative. A successful prediction confirms that the theory does work in the world, that it has relevance beyond its own statements. A failed prediction signals a lacuna, a point where theory must be reconsidered. Prediction is, therefore, both epistemic and existential: it is how theories stake their claim upon reality.

Yet, as we move into modern physics, this intuitive sense begins to fray. The language of prediction persists, but the underlying temporal and experiential commitment is quietly loosened. The term “prediction” is increasingly invoked in contexts where anticipation is abstracted from occurrence, and where the bridge to experience is indirect at best.

Understanding what is at stake requires that we first stabilise what prediction used to mean. Only then can we see how it mutates — from temporal commitment to formal exercise, from empirical engagement to internal credential, from anticipation to badge of legitimacy.

This is the starting point of our series: to map the drift of prediction, to see the mechanisms by which it transforms, and to understand the subtle ways in which theoretical authority is maintained even as the connection to phenomena recedes.