[mikegi]

Here's a sort of spin-off on Zeno:

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It is impossible for a differential equation to indicate cause and effect without involving instantaneous action at a distance

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For example, one of Maxwell's equations for a plane wave is dE/dx = -dB/dt. Does this equation say that a change in time of B at a point **causes** a change in E with distance??? Then there's the counterpart to this equation: c^2 dB/dx = dE/dt. Does this say that a change in E with time **causes** a change in B with distance?

A lot of people think so, even the supposedly great Feynman: "It is impossible for them to disappear. They maintain themselves in a kind of dance - one making the other, the second making the first - propagating onward through space". This the "rolling wave" description of Maxwell's Equations.

But, how can this work? How does a value at a point *know* that it is changing with time? It can't because it would instantaneously need to know two things: what it was before and what it is going to be. Worse still is to add on the idea that this change at a point with time *causes* a change in something else with distance.

[Another bong hit]

So, is it possible for a differential equation to indicate cause and effect?

[RightWhale]

That isn't really action at a distance. It is measurement along two dimensions, along the axis of time and along the axis of space. Movement on one axis, mathematically speaking is accompanied by movement on the other axis, mathematically speaking. Not causation, but confusion; one is the time equivalent of the other, and the other is the space equivalent of the first. Measurement is a process, so physical quantities are inherently processes. B and E are one thing seen as separate processes, just measured differently because there is more than one way to measure things.