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Is life a form of computation?

(thereader.mitpress.mit.edu)
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AIPedant ◴[] No.45353525[source]
Articles like this indicate we should lock down the definition of "computation" that meaningfully distinguishes computing machines from other physical phenomena - a computation is a process that maps symbols (or strings of symbols) to other symbols, obeying certain simple rules[1]. A computer is a machine that does computations.

In that sense life is obviously not a computation: it makes some sense to view DNA as symbolic but it is misleading to do the same for the proteins they encode. These proteins are solving physical problems, not expressing symbolic solutions to symbolic problems - a wrench is not a symbolic solution to the problem of a symbolic lug nut. From this POV the analogy of DNA to computer program is just wrong: they are both analogous to blueprints, but not particularly analogous to each other. We should insist that DNA is no more "computational" than the rules that dictate how elements are formed from subatomic particles.

[1] Turing computability, lambda definability, primitive recursion, whatever.

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jes5199 ◴[] No.45353938[source]
our relationship to computation got weird when we moved to digital computers. Like, I don’t think anyone was saying “life is like millions of slide-rules solving logarithms in parallel”. but now that computers are de-materialized, they can be a metaphor for pretty much anything
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1. mannykannot ◴[] No.45355152[source]
Good point - maybe the analogy to computation arises simply because digital computation and the synthesis of DNA, RNA and proteins are all performed by discrete-state machines?
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2. jes5199 ◴[] No.45355255[source]
does DNA/RNA keep state other than the position of the read head?
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3. mannykannot ◴[] No.45359990[source]
Not as far as I know, but that is not saying much.