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by defrost 264 days ago
There's a confusion of nomenclature.

Computers are functional mappings from inputs to outputs, sure.

Analog fire computers are continuous mappings from a continuum, a line segment (curved about a cam), to another continuum, a dial perhaps.

Symbolic operations, mapping from patterns of 0s and 1s (say) to other patterns are discrete, countable mappings.

With a real valued electrical current, discrete symbols are forced by threshold levels.

2 comments

> Analog fire computers are continuous mappings from a continuum, a line segment (curved about a cam), to another continuum, a dial perhaps.

> Symbolic operations, mapping from patterns of 0s and 1s (say) to other patterns are discrete, countable mappings.

What definition of "symbolic" are you using that draws a distinction between these two cases? If it means merely something that symbolises something else (as I would usually use it), then both a position on a line segment and a pattern of voltage levels qualify. If you mean it in the narrow sense of a textual mark, that pattern of voltage levels is just as much not a "symbol" as the position on the line segment.

To what degree is the threshold precise? Maybe fundamentally there's not that much difference.