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Comment by danghica | Hacker News Reader

If "everything computes" then you can not use "because it computes" as an explanation.

I do not see how this is a bad thing. It seems incorrect at some level, but claiming that things that compute are somehow categorically different is an appeal to magical thinking.

I would agree that claiming that a rock computes by not simply vanishing from one plank time to the next is not satisfying. This leads me to think that computation has much more to do with whether a particular being has reach a thermodynamic local minimum than anything else (lava does not compute since, despite being far more active than a rock, its behaviour can be explained by the fact that it is a couple thousand degrees hotter than a normal rock). Energy dissipation also does not fit the bill since stars dissipate energy but do not compute.

Unfortunately the thinking surrounding things like proteins look incredibly similar, their behavior changes as a function of ph and temperature, and most arguments that a protein computes are based on defining a function for that protein. This gets us nowhere, but it does suggest that it may not be possible to define computation in a way that excludes systems dissipating energy to reach thermodynamic local minima.

Re: "claiming that things that compute are somehow categorically different is an appeal to magical thinking" - This is not the case. The distinction that's being made is one of perspective and purpose, i.e. implementing method to get result. Or am I getting this wrong?

You are getting it correct, but the idea that computation is defined based on some purpose or from a limited subset of all perspectives is exactly what I take issue with. If your notion of computation is dependent on purpose and thus some teleological notion of function then saying something computes doesn't tell us anything about that being, only about how human beings perceive that being and its function. Again, this undermines the usefulness of having a perspective/function independent notion of computation. The magical thinking arises because we project our notations of function onto the being itself and conflate our uses for that being with the intrinsic properties of that being. Purposes/uses/functions are not intrinsic properties. Computation may not be an intrinsic property, it may only be a relational property, which would be an interesting result itself, but probably quite irritating to people who want to make arguments that there is something intrinsically different about certain kinds of systems.

Which is good, as that is indeed an unsatisfying explanation. You can, however talk about _what_ it computes and _how_ it computes, which might be interesting or useful explanations.

Yes, of course. But that is not the point at stake here.

Who is using "because it computes" as an explanation for anything? And to explain what?

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