“All philosophers, of every school, imagine that causation is one of the fundamental axioms of science, yet, oddly enough, in advanced science … the word ‘cause’ never occurs …. The Law of Causality, I believe, like much that passes among philosophers, is a relic of a by-gone age, surviving like the monarchy, only because it is erroneously supposed to do no harm.”—Bertrand Russell (1928)

Causality is an invention of the formal reason, a product of philosophers and scientists. As an idea, however, “cause” finds its basis in ordinary experience. Objects move. How? By being acted upon by other objects or by human agency; exert a pull here, create an effect there. In the world of experience unrefined by science or philosophy, it sometimes seems as if every thing is connected in some way with every other thing, all are parts in a cosmic puppet show. A simple string model appears natural and true and is a prototype of common-sense notions of causality. Even in science, at least until recently, such notions were given expression as well. The string model, for instance, was to be found equally in the simplest interpretations of Newtonian mechanics as in the implicit theories of the carpenter, the plumber, or the agriculturist. Particles exist and forces act between them as causes, producing change. The very idea of force introduces a feeling of compulsion and the causal connection between events seems a physical necessity, reinforcing the lessons taught by every-day experience.