If you say that there is a property X of computation that occurs independently of how the computation is actually carried out, whether it's by a current generation CPU, hydraulics, lego blocks, someone writing values and following instructions on index cards or some other method that no one has even thought of yet then that property is an abstract property of computation. That's all the word "abstract" means in this context.
What you are suggesting would be like saying that there's some property of addition that is not mathematical (because hopefully we agree that mathematics only studies abstract properties) but that you can only learn about by looking at all the different kinds of things that one can concretely apply addition to.
I would argue that such a thing is implausible. It would be completely unlike anything that anyone has seen in the real world.
One thing I think we do agree on is that conscious experiences are not abstract (very unlike the other person I've been exchanging comments with who denies that they even exist at all). Beyond that I argue that computation itself is entirely abstract and though I don't seem to be able to get you to admit that, I think most people, certainly most computer scientists would admit it readily.
So what we're left with is a claim that an abstract process can produce something that is not abstract and such claims are just not plausible. That would be exactly like a computer simulation of the weather producing actual water.
>If you say that there is a property X of computation that occurs independently of how the computation is actually carried out... That's all the word "abstract" means in this context.
Ok, that makes sense, sure.
>...because hopefully we agree that mathematics only studies abstract properties...
I can't agree, performing a calculation isn't an abstract concept, it's a physical process. It does map to abstract concepts though.
>Beyond that I argue that computation itself is entirely abstract and though I don't seem to be able to get you to admit that, I think most people, certainly most computer scientists would admit it readily.
That is not the case. The fact that computation is fundamentally a physical process is a core principle of several branches of physics and computer science:
Computers aren't abstract, they're real objects doing things in the real world. If the thing they are physically doing is not computation, what is it?
>So what we're left with is a claim that an abstract process can produce something that is not abstract and such claims are just not plausible. That would be exactly like a computer simulation of the weather producing actual water.
Abstractions cannot affect the real world, sure, so if computation is purely abstract how come your computer can display my message on your physical screen right now? How is that happening, if not by computation?
You're really tangling yourself up in knots with this view of abstraction. You can map what happens in a computer against abstract concepts and abstract objects yes. You can also map operations in several different physical systems against the same abstract objects. That's what it means when we say computation is implementation independent. But it still needs to be implemented to actually happen.
Previously you said this:
>Computation is not a physical process any more than addition is a physical process. It is true that to actually perform either a physical instantiation is necessary...
So it's not a physical process, but you can instantiate it. And it's purely abstract so can't affect the physical world. Yet here we are using computers.
I don't think there's much point in continuing this thread since we obviously have very different ways of conceptualizing reality.
I will say one more thing however:
I never said that abstractions cannot affect the physical world, I said that they cannot produce non-abstract things. A computation can affect the physical world by modulating the flow of electrons (which already existed, they were not created by the computation) to an output device, such as a screen that will display something you can see. But everything described in that last sentence isn't part of the abstract computation itself, it's a side-effect when the computation is run on a particular type of hardware. If instead you ran the same program using a human computer, as Alan Turing suggested in his well known paper on the halting problem, which largely created the field of computer science, then the result would not be displayed on a screen but instead perhaps written on a piece of paper. Nonetheless it's the same computation that was run in both cases. That's why computation is intrinsically abstract by nature.
What you are suggesting would be like saying that there's some property of addition that is not mathematical (because hopefully we agree that mathematics only studies abstract properties) but that you can only learn about by looking at all the different kinds of things that one can concretely apply addition to.
I would argue that such a thing is implausible. It would be completely unlike anything that anyone has seen in the real world.
One thing I think we do agree on is that conscious experiences are not abstract (very unlike the other person I've been exchanging comments with who denies that they even exist at all). Beyond that I argue that computation itself is entirely abstract and though I don't seem to be able to get you to admit that, I think most people, certainly most computer scientists would admit it readily.
So what we're left with is a claim that an abstract process can produce something that is not abstract and such claims are just not plausible. That would be exactly like a computer simulation of the weather producing actual water.
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