Popper: Of Clouds and Clocks - Freedom and Determinism

This is the central philosophical problem Popper aims to solve: How can abstract meanings, ideas, promises, or theories - which have no mass, no energy, no physical properties - causally influence physical behavior? Compton's example: He traveled from Italy to Yale to deliver a lecture because of a *promise* he had made. But a promise is an abstract entity - just marks on paper or sounds in air. How can these abstractions make a physical system (his body) travel thousands of miles? A strict physicalist would have to say: A physicist who knew Compton's exact physical state could have predicted his journey purely from particle positions and velocities, without knowing anything about promises, meanings, or Yale lectures. The promise is just an "epiphenomenon" - a byproduct with no real causal power. But this seems absurd. Clearly the *content* of the promise (not just its physical embodiment) matters causally. If the promise had been to meet in Paris instead of New Haven, Compton would have gone to Paris. The abstract content controls the physical behavior. How is this possible without postulating mysterious mental substances or violating physical laws? This is Compton's Problem, and it's more fundamental than the traditional mind-body problem. It's about how the abstract realm of meanings, arguments, and ideas can have genuine causal efficacy in the physical world.

Popper's solution begins with understanding "plastic controls" - control mechanisms that are neither rigidly determined nor purely random. Consider a soap bubble: The enclosed air molecules move chaotically (cloud-like), but they're controlled by the film envelope. Yet this control is *plastic* - the film flexibly adjusts to environmental changes, maintaining the bubble while allowing variation. The film doesn't rigidly determine each molecule's path; it sets boundaries and constraints that the chaotic motion explores. Or consider a driver steering a car: The driver doesn't control every spark plug firing or piston movement. The lower-level mechanisms operate automatically (even randomly in their microscopic details). But the driver's steering provides *top-down control* through a hierarchy - intentions influence steering wheel position, which influences wheel direction, which influences car trajectory - all while leaving enormous freedom at lower mechanical levels. Plastic controls have three key features: 1. **Hierarchical organization**: Multiple levels where higher levels constrain (but don't fully determine) lower levels 2. **Feed-back sensitivity**: The system responds to its environment and its own outputs 3. **Exploiting indeterminacy**: Rather than eliminating randomness, plastic controls use the freedom at lower levels to explore possibilities This concept dissolves the false dichotomy between rigid determinism and pure chance. Freedom emerges in systems with plastic controls - systems that are organized hierarchically and can respond to abstract considerations while remaining physically embodied.