Re: the perfect deterministic twin prisoner’s dilemma:
You’re a deterministic AI system, who only wants money for yourself (you don’t care about copies of yourself). The authorities make a perfect copy of you, separate you and your copy by a large distance, and then expose you both, in simulation, to exactly identical inputs (let’s say, a room, a whiteboard, some markers, etc). You both face the following choice: either (a) send a million dollars to the other (“cooperate”), or (b) take a thousand dollars for yourself (“defect”).
If we say there are two atoms in two separate rooms, with the same initial positions and velocities, we of course can’t talk about the atoms “choosing” to fly one direction or another. And yet the two atoms will always “do the same thing”. Does the movement of one of the atoms “cause” the movement of the other atom? No, the notion of “cause” is not a concept that has meaning at this layer of description of reality. There is no cause, just atoms obeying the equations of motion.
Similarly: If we say two people are the same at the atomic (or whatever) level, we can no longer speak about a notion of “choice” at all. To talk about choice is to mix up levels of abstraction.
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Let me restate it another way.
“Choice” is not a concept that exists at the ground level of reality. There is no concept of “choice” in the equations of physics. “Deciding to make a choice” can only be discussed at a higher level of abstraction; but insisting that my twin and I run the same code is talking at a lower level, at the ground truth of reality.
If we’re talking at that lower level, there *is no notion of choice*.
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Restated yet another way: Since the attempted discussion is at two different levels of reality, the situation is just ill-posed (a la “what happens when an unstoppable force meets an unmovable object”).
(Or as you put it: “various questions tend to blur together here – and once we pull them apart, it’s not clear to me how much substantive (as opposed to merely verbal) debate remains.”)
Similarly: If we say two people are the same at the atomic (or whatever) level, we can no longer speak about a notion of “choice” at all. To talk about choice is to mix up levels of abstraction.
This doesn’t make any sense to me. People are made of atoms. People make choices. Nothing is inconsistent about that. If two people were atomically identical, they’d make the same choices. But that wouldn’t change anything about how the choice was happening. Right?
Suppose we made an atom-by-atom copy of you, as in the post. Does the existence of this copy mean that you stop choosing your own decisions?
Thanks, this gives me another chance to try to lay out this argument (which is extra-useful because I don’t think I’ve hit upon the clearest way of making the point yet):
People are made of atoms. People make choices. Nothing is inconsistent about that.
Absolutely. But “choice”, like agency, is a property of the map not of the territory. If you full specify the initial position of all of the atoms making up my body and their velocities, etc. -- then clearly it’s not useful to speak of me making any choices. You are in the position of Laplace’s demon: you know where all my atoms are right now, you know where they will be in one second, and the second after that, and so on.
We can only meaningfully talk about the concept of choice from a position of partial ignorance.
(Here I’m speaking from a Newtonian framing, with atoms and velocities, but you could translate this to QM.)
Similarly. If you performed your experiment and made an atom-by-atom copy of me, then you know that I will make the same choice as my clone. It doesn’t make sense to talk from your perspective about how I should make my “choice”—what I and my clone will do is already baked in by the law of motion for my atoms, from the assumption that you know we’re atom-by-atom copies.
(If “I” am operating from an ignorant perspective, then “I” can still talk about “making a choice” from “my” perspective.)
Does that make sense, do you see what I’m trying to say? Do you see any flaws if so?
Here’s a related old comment from @Anders_H that I think frames the issue nicely, for my own reference at the very least:
Any decision theory depends on the concept of choice: If there is no choice, there is no need for a decision theory. I have seen a quote attributed to Pearl to the effect that we can only talk about “interventions” at a level of abstraction where free will is apparent. This seems true of any decision theory.
(He goes on to say—less relevantly for the discussion here, but again I like the framing so am recording to remind future-me—“CDT and TDT differ in how they operationalize choice, and therefore whether the decision theories are consistent with free will. In Causal Decision theory, the agents choose actions from a choice set. In contrast, from my limited understanding of TDT/UDT, it seems as if agents choose their source code. This is not only inconsistent with my (perhaps naive) subjective experience of free will, it also seems like it will lead to an incoherent concept of “choice” due to recursion.”)
Re: the perfect deterministic twin prisoner’s dilemma:
If we say there are two atoms in two separate rooms, with the same initial positions and velocities, we of course can’t talk about the atoms “choosing” to fly one direction or another. And yet the two atoms will always “do the same thing”. Does the movement of one of the atoms “cause” the movement of the other atom? No, the notion of “cause” is not a concept that has meaning at this layer of description of reality. There is no cause, just atoms obeying the equations of motion.
Similarly: If we say two people are the same at the atomic (or whatever) level, we can no longer speak about a notion of “choice” at all. To talk about choice is to mix up levels of abstraction.
---
Let me restate it another way.
“Choice” is not a concept that exists at the ground level of reality. There is no concept of “choice” in the equations of physics. “Deciding to make a choice” can only be discussed at a higher level of abstraction; but insisting that my twin and I run the same code is talking at a lower level, at the ground truth of reality.
If we’re talking at that lower level, there *is no notion of choice*.
---
Restated yet another way: Since the attempted discussion is at two different levels of reality, the situation is just ill-posed (a la “what happens when an unstoppable force meets an unmovable object”).
(Or as you put it: “various questions tend to blur together here – and once we pull them apart, it’s not clear to me how much substantive (as opposed to merely verbal) debate remains.”)
This doesn’t make any sense to me. People are made of atoms. People make choices. Nothing is inconsistent about that. If two people were atomically identical, they’d make the same choices. But that wouldn’t change anything about how the choice was happening. Right?
Suppose we made an atom-by-atom copy of you, as in the post. Does the existence of this copy mean that you stop choosing your own decisions?
Have I just misunderstood what you’re saying?
Thanks, this gives me another chance to try to lay out this argument (which is extra-useful because I don’t think I’ve hit upon the clearest way of making the point yet):
Absolutely. But “choice”, like agency, is a property of the map not of the territory. If you full specify the initial position of all of the atoms making up my body and their velocities, etc. -- then clearly it’s not useful to speak of me making any choices. You are in the position of Laplace’s demon: you know where all my atoms are right now, you know where they will be in one second, and the second after that, and so on.
We can only meaningfully talk about the concept of choice from a position of partial ignorance.
(Here I’m speaking from a Newtonian framing, with atoms and velocities, but you could translate this to QM.)
Similarly. If you performed your experiment and made an atom-by-atom copy of me, then you know that I will make the same choice as my clone. It doesn’t make sense to talk from your perspective about how I should make my “choice”—what I and my clone will do is already baked in by the law of motion for my atoms, from the assumption that you know we’re atom-by-atom copies.
(If “I” am operating from an ignorant perspective, then “I” can still talk about “making a choice” from “my” perspective.)
Does that make sense, do you see what I’m trying to say? Do you see any flaws if so?
Here’s a related old comment from @Anders_H that I think frames the issue nicely, for my own reference at the very least:
(He goes on to say—less relevantly for the discussion here, but again I like the framing so am recording to remind future-me—“CDT and TDT differ in how they operationalize choice, and therefore whether the decision theories are consistent with free will. In Causal Decision theory, the agents choose actions from a choice set. In contrast, from my limited understanding of TDT/UDT, it seems as if agents choose their source code. This is not only inconsistent with my (perhaps naive) subjective experience of free will, it also seems like it will lead to an incoherent concept of “choice” due to recursion.”)