Consequently, insofar as decision theory is about determining which decision is rational, on this account CDT reasons correctly in Newcomb’s problem.
I think this is only correct if you accept the CDT view of what a decision actually is—i.e. that decisions are made at a particular point in space-time and can be made one way or the other independently of what happens in the rest of the world.
If you instead define decisions as occurring at some point in algorithms-we-haven’t-yet-computed space, I think you’ll end up with something TDT-like in either case—whether you focus on making the rational decision or being the rational agent.
Yes, though this is just a FAQ section dealing with the “standard” view on how decision theory and winning interact and the reason that proponents of CDT hold their position even though they think winning is important. Perhaps that’s all there is and there’s no lesson to be had from it other than “this is what lots of philosophers think”.
Personally, however, I think it reveals more than this. People who are new to the debate sometimes have the following view about CDT:
CDT loses in NP and then proponents of CDT just whine about NP by complaining about predictors that punish rational people.
(Of particular note, some people take this claim as a a basic, obvious fact—as opposed to others who reach this conclusion at the end of a long argument for the position).
However, I think the proponent of CDT actually holds a more subtle position than this (which is partly outlined in the FAQ section above). As your comment highlights, the question then becomes a complex one about which view of decisions we should accept. The answer to this debate is likely to be motivated in part by the result of a debate about which technical definition of winning we should accept (technical because we’re not just counting average utility received by agents because if we did then not chewing in the chewing gum problem would come out as rational). The above section reveals that the proponent of CDT has their own views about what definition of winning matters in decision theory, just as the proponent of TDT does (it’s not that one simply doesn’t care about winning) and so it seems to me that the debate requires more steps to reach the above view than simply accepting it at face value.
CDT loses in NP and then proponents of CDT just whine about NP by complaining about predictors that punish rational people.
I don’t actually disagree with this statement (except its tone) - but in order to have rational debates we need to [construct the strongest possible version of the opposite view|http://lesswrong.com/lw/85h/better_disagreement/] before we have a go at demolishing it. So with that in mind, I definitely like the way CDT is being framed here.
I just brought this up because I wasn’t sure whether the original sentence I quoted was painted with “this sentence has lukeprog/crazy88′s unconditional support” or “this sentence belongs as part of the CDT philosophy”.
Is it worth mentioning (in a different section) the problems of reconciling the CDT model of a “decision” with reductionism? i.e. no matter how small you grind up the physical universe, you won’t find anything that looks like a “decision”, but you can grind up algorithm space until you find something that looks like “you”. Or is this too advanced (or nonsensical) for the FAQ?
I agree. In terms of my statement regarding those who hold that:
CDT loses in NP and then proponents of CDT just whine about NP by complaining about predictors that punish rational people.
My claim wasn’t that this wasn’t a suitable conclusion but rather that it wasn’t a suitable starting point. As you note, it’s good to construct a steel man of an opponent’s argument before attacking it but even more crucially, it’s important that we don’t attack straw men. The view of CDT in the FAQ isn’t even a steel man, it’s just the position advocated by many proponents of CDT. Attacking anything weaker than this is attacking a straw man. So proponents of CDT may whine that NP punishes irrational agents but they at least have an argument as to why NP punishes irrational agents as well. Ignoring this argument while attacking its conclusion is undesirable.
(That’s all just a statement of what we seem to be agreeing about).
I just brought this up because I wasn’t sure whether the original sentence I quoted was painted with “this sentence has lukeprog/crazy88′s unconditional support” or “this sentence belongs as part of the CDT philosophy”.
Definitely not—this section of the FAQ is summarising a popular view, not endorsing it. I took the words “on this account” to mean that the statement wasn’t being endorsed but rather a particular account being summarised. However, perhaps this could be made more clear (as follows?)
Consequently, the proponent of CDT will argue that, insofar as decision theory is about determining which decision is rational, CDT reasons correctly in Newcomb’s problem.
In terms of this:
Is it worth mentioning (in a different section) the problems of reconciling the CDT model of a “decision” with reductionism?
The FAQ is meant to be more of a basic level introduction to decision theory so I’m not sure if this is the place for it. But Luke’s the one who knows the master plan.
I think this is only correct if you accept the CDT view of what a decision actually is—i.e. that decisions are made at a particular point in space-time and can be made one way or the other independently of what happens in the rest of the world.
If you instead define decisions as occurring at some point in algorithms-we-haven’t-yet-computed space, I think you’ll end up with something TDT-like in either case—whether you focus on making the rational decision or being the rational agent.
Yes, though this is just a FAQ section dealing with the “standard” view on how decision theory and winning interact and the reason that proponents of CDT hold their position even though they think winning is important. Perhaps that’s all there is and there’s no lesson to be had from it other than “this is what lots of philosophers think”.
Personally, however, I think it reveals more than this. People who are new to the debate sometimes have the following view about CDT:
(Of particular note, some people take this claim as a a basic, obvious fact—as opposed to others who reach this conclusion at the end of a long argument for the position).
However, I think the proponent of CDT actually holds a more subtle position than this (which is partly outlined in the FAQ section above). As your comment highlights, the question then becomes a complex one about which view of decisions we should accept. The answer to this debate is likely to be motivated in part by the result of a debate about which technical definition of winning we should accept (technical because we’re not just counting average utility received by agents because if we did then not chewing in the chewing gum problem would come out as rational). The above section reveals that the proponent of CDT has their own views about what definition of winning matters in decision theory, just as the proponent of TDT does (it’s not that one simply doesn’t care about winning) and so it seems to me that the debate requires more steps to reach the above view than simply accepting it at face value.
I don’t actually disagree with this statement (except its tone) - but in order to have rational debates we need to [construct the strongest possible version of the opposite view|http://lesswrong.com/lw/85h/better_disagreement/] before we have a go at demolishing it. So with that in mind, I definitely like the way CDT is being framed here.
I just brought this up because I wasn’t sure whether the original sentence I quoted was painted with “this sentence has lukeprog/crazy88′s unconditional support” or “this sentence belongs as part of the CDT philosophy”.
Is it worth mentioning (in a different section) the problems of reconciling the CDT model of a “decision” with reductionism? i.e. no matter how small you grind up the physical universe, you won’t find anything that looks like a “decision”, but you can grind up algorithm space until you find something that looks like “you”. Or is this too advanced (or nonsensical) for the FAQ?
I agree. In terms of my statement regarding those who hold that:
My claim wasn’t that this wasn’t a suitable conclusion but rather that it wasn’t a suitable starting point. As you note, it’s good to construct a steel man of an opponent’s argument before attacking it but even more crucially, it’s important that we don’t attack straw men. The view of CDT in the FAQ isn’t even a steel man, it’s just the position advocated by many proponents of CDT. Attacking anything weaker than this is attacking a straw man. So proponents of CDT may whine that NP punishes irrational agents but they at least have an argument as to why NP punishes irrational agents as well. Ignoring this argument while attacking its conclusion is undesirable.
(That’s all just a statement of what we seem to be agreeing about).
Definitely not—this section of the FAQ is summarising a popular view, not endorsing it. I took the words “on this account” to mean that the statement wasn’t being endorsed but rather a particular account being summarised. However, perhaps this could be made more clear (as follows?)
In terms of this:
The FAQ is meant to be more of a basic level introduction to decision theory so I’m not sure if this is the place for it. But Luke’s the one who knows the master plan.