wtf wrote: ↑Tue May 21, 2019 3:55 am
The issue on the table (for me at this moment) is your statement that the mind (ok I said brain earlier but hey, if you think the universe is a computer then why would you even think there's a difference) ... you said that the mind computes but is not a computer. I'm trying to discern if you mean.
Because I said 'the universe is a computer' I thought I had given you enough to deduce that everything within the universe computes also.
wtf wrote: ↑Tue May 21, 2019 3:55 am
* The mind computes but is not a computer because computation is ONE of the things it does, just as a washer-dryer dries clothes but is not exclusively a dryer; and that the mind might do some OTHER thing as well. In which case I ask what that other thing is. Like the washer-dryer also washes.
* Or ... well exactly what, I'm not sure. If the mind computes but is not a computer, what can that mean?
It means simply that I understand how the first sentence in the conversation frames the context of discussion, and once a frame is established it brings with it the concepts/language/discourse associated with that frame of mind. And since we are on a philosophy forum I wanted to make sure we are talking about what X DOES, not what X is. Because I am acutely aware of the
ontological error of philosophy
That was it. You read too much into it.
I could've said "the brain is just a bunch of quarks, leptons and bosons" and then the conversation would've gone in a different direction.
wtf wrote: ↑Tue May 21, 2019 3:55 am
Not to me.
OK. Then the sentence "the mind computes but is not a computer " was not targeted at you.
To somebody who understands computation abstractly I wouldn't even utter it. I measure my language depending on my interlocutor's background knowledge.
wtf wrote: ↑Tue May 21, 2019 3:55 am
I'm happy to stipulate that by computer we mean a Turing machine. Either an abstract one as in Turing 1936; or else a practical implementation exactly like the one on my lap. Do you agree that a computer is a TM? Or do you prefer a different definition and if so, what?
Because you have a background in Mathematics I am happy to go even more abstract. Church's Lambda calculus is a generalization of TMs.
And perhaps this is the crux of my argument. If you can describe the behaviour/function of the system in terms of λ-calculus - it computes.
Which is why I am interested in HoTT at present, because everything about HoTT screams "computation".
Hell. Everything about Univalent Mathemeatics screams "computation":
https://github.com/UniMath/UniMath
wtf wrote: ↑Tue May 21, 2019 3:55 am
Are those different than Turing machines? Do they break the Church-Turing thesis?
The only difference is finite memory. Which, in turn, has implication on all the mathematics that follow when it comes to dealing with the Real numbers when we start making range/precision trade-offs, computational complexity, representational complexity (Kolmogorov) etc
But the language I used was targeted at the general public, who might find the idea that your mind is "just like the PC on your desk" rather unsettling and inhumane thing to say. For somebody with an identity crisis, and lack of theoretical grounding it can be a little unnerving.
wtf wrote: ↑Tue May 21, 2019 3:55 am
Ok. But the claim that the universe is a computer is a
metaphysical claim that is entirely separate from any particular aspect of math or computer science or physics.
It stops being a separate issue the moment we attempt to describe it in language.
Our description of the universe (however incomplete) are computational in nature.
In fact, I can't fathom a Mathematical model of any kind that is not computational.
If you can describe it in Mathematics - it computes some consequences. Input/output.
wtf wrote: ↑Tue May 21, 2019 3:55 am
And in any event, if you think that the universe is a computer then so is the mind; in which case why did you object to my interchanging brain with mind earlier? To you they should be exactly the same thing. Or if not, how are they different?
I am merely trying to draw the line somewhere. When we talk about brains we bring in all the complexity of molecular biology and neuroscience to the table. Since we are dealing with "functional equivalence" I am trying to abstract it away unless absolutely necessary and focus on question like "What is the function of the mind?" and "Who decides and how if a particular machine is functionally equivalent to a mind?"
I am trying to extract a utility function.
wtf wrote: ↑Tue May 21, 2019 3:55 am
Yes my point exactly. I myself am perfectly happy to distinguish minds from brains. But I don't believe the worlds' a computer. If one does believe that, then how can they distinguish between minds and brains?
I can observe many brains. I can observe only one mind. I can communicate with many minds. I cannot communicate with any brains.
But it is precisely because it is difficult to draw a distinction between MY brain and MY mind is why I am trying to settle the "functional equivalence" question. What is the function of the mind exactly? I am happy to use "computation" as point of departure - if you have a more useful model, I am happy to hear it.
I am also happy with "if it can do what I do" then it's an accurate description of my mind. Speakpigeon seems to expects more (than functional equivalence) even though he claims that's sufficient. Apparently autonomous vehicles aren't doing what minds do.
wtf wrote: ↑Tue May 21, 2019 3:55 am
Well even that is a metaphysical speculation. Some people think that minds are what brains do. Others think that minds are what computations do.
If you subscribe to
model-dependent realism it's ALL metaphysical speculation.
The model that you have chosen directly influences the language you use to speak about X. It's about utility, not truth. I am the epitome of a model-dependent realist - I Interpret everything through the framework of computation.
Despite its name, it's actually an anti-realist position. We have no direct access to reality - we only have models of reality.
When I say that "the mind is a computer" I can now go onto use all of the languages of computation to speak about the internal structures of my mind.
Such as describing my "stale beliefs" as
cache invalidation problems.
Or saying that notion of God is a
Null pointer.
Or talk about
context switching in much more detail than its colloquial meaning.
Or use the models of
distributed systems to talk about organisational/inter-human communication failures.
Or we can use the language/algorithms/strategies from
error detection/correction to improve communication.
Metaphysical consensus is a bloody useful thing in a collaborative environment!
wtf wrote: ↑Tue May 21, 2019 3:55 am
There's no proof that our brains are digital computers and plenty of evidence that they're not.
Proof, eh? You mean the process of hypothesis-testing, the process of updating one's beliefs as new information arrives?
That's what we use
Bayesian machine learning for...
If we are talking about functional equivalence - none of the above maters, we are necessarily talking about instrumentalism. If you can make a computational machine (digital, mechanical, quantum-mechanical, chemical or biological) that performs some task as well as the human mind does then you have described the logic of some part of the human mind.
https://en.wikipedia.org/wiki/Realization_(systems)
In systems theory, a realization of a state space model is an implementation of a given input-output behavior.