Said literature gives advice, reasoning and conclusions that is epistemically, instrumentally and normatively bad.
This is a recurring issue, so perhaps my instructor and textbooks were atypical: we never discussed or even cared whether someone should defect on PD in my game theory course. The bounds were made clear to us in lecture – game theory studies concepts like Nash equilibria and backward induction (using the term ‘rationality’ to mean VNM-rationality) and applies them to situations like PD; that is all. The use of any normative language in homework sets or exams was pretty much automatically marked incorrect. What one ‘should’ or ‘ought’ to do were instead relegated to other courses in, e.g, economics, philosophy, political science. I’d like to know from others if this is a typical experience from a game theory course (and if anyone happens to be working in the field: if this is representative of the literature).
And the common usage of ‘rational’ on lesswrong should be different to what is used in a significant proportion of game theory literature.
No. The themes of epistemic and instrumental rationality are the foundational premise of the site. It is right there in the tagline on the top of the page. I oppose all attempts to replace instrumental rationality with something that involves doing stupid things.
Upon reflection, I tend to agree with these statements. In this case, perhaps we should taboo ‘rationality’ in its game theoretic meaning – use the phrase ‘VNM-rationality’ whenever that is meant instead of LW’s ‘rationality’.
How about let’s not taboo anything, just make it clear up front what is meant when really necessary. I would prefer that because I think such taboos contribute to the entry barrier for every LW newcomer; I don’t want newcomers used to the game-theoretic jargon to keep unwittingly running afoul of this and getting downvoted.
Perhaps it would be useful if Yvain inserted a clarification of this early in the Sequence.
The use of any normative language in homework sets or exams was pretty much automatically marked incorrect.
The normative claim is one I am making now about the ‘rationality’ theories in question. It is the same kind of normative claim I make when I say “empirical tests are better than beliefs from ad baculum”.
Upon reflection, I tend to agree with these statements. In this case, perhaps we should taboo ‘rationality’ in its game theoretic meaning – use the phrase ‘VNM-rationality’ whenever that is meant instead of LW’s ‘rationality’.
I could agree to that—conditional on confirmation from one of the Vladimirs that the axioms in question do, in fact, imply the faux-rational (CDT like) conclusions the term would be used to represent. I don’t actually see it at a glance and would expect another hidden assumption to be required. I wouldn’t be comfortable using the term without confirmation.
The normative claim is one I am making now about the ‘rationality’ theories in question.
I quoted badly; I believe there was a misunderstanding. The first quote in the parent to this should be taken in the context of your sentence segment that “Said literature gives advice”. In my paragraph, I was objecting to this from my experiences in my course, where I did not receive any advice on what to do in games like PD. Instead, the type of advice that I received was on how to calculate Nash equilibria and find SPNEs.
Otherwise, I am mostly in agreement with the latter part of that sentence. (ETA: That is, I agree that if current game theoretic equilibrium solutions are taken as advice on what one ought to do, then that is often epistemically, instrumentally, and normatively bad.)
More ETA:
conditional on confirmation from one of the Vladimirs that the axioms in question do, in fact, imply the faux-rational (CDT like) conclusions the term would be used to represent. I don’t actually see it at a glance and would expect another hidden assumption to be required.
You are correct – VNM-rationality is incredibly weak (though humans don’t satisfy it). It is, after all, logically equivalent to the existence of a utility function (the proof of this by von Neumann and Morgenstern led to the eponymous VNM theorem). The faux-rationality on LW and in popular culture requires much stronger assumptions. But again, I don’t think these assumptions are made in the game theory literature – I think that faux-rationality is misattributed to game theory. The game theory I was taught used only VNM-rationality, and gave no advice.
This is a recurring issue, so perhaps my instructor and textbooks were atypical: we never discussed or even cared whether someone should defect on PD in my game theory course. The bounds were made clear to us in lecture – game theory studies concepts like Nash equilibria and backward induction (using the term ‘rationality’ to mean VNM-rationality) and applies them to situations like PD; that is all. The use of any normative language in homework sets or exams was pretty much automatically marked incorrect. What one ‘should’ or ‘ought’ to do were instead relegated to other courses in, e.g, economics, philosophy, political science. I’d like to know from others if this is a typical experience from a game theory course (and if anyone happens to be working in the field: if this is representative of the literature).
Upon reflection, I tend to agree with these statements. In this case, perhaps we should taboo ‘rationality’ in its game theoretic meaning – use the phrase ‘VNM-rationality’ whenever that is meant instead of LW’s ‘rationality’.
How about let’s not taboo anything, just make it clear up front what is meant when really necessary. I would prefer that because I think such taboos contribute to the entry barrier for every LW newcomer; I don’t want newcomers used to the game-theoretic jargon to keep unwittingly running afoul of this and getting downvoted.
Perhaps it would be useful if Yvain inserted a clarification of this early in the Sequence.
The normative claim is one I am making now about the ‘rationality’ theories in question. It is the same kind of normative claim I make when I say “empirical tests are better than beliefs from ad baculum”.
I could agree to that—conditional on confirmation from one of the Vladimirs that the axioms in question do, in fact, imply the faux-rational (CDT like) conclusions the term would be used to represent. I don’t actually see it at a glance and would expect another hidden assumption to be required. I wouldn’t be comfortable using the term without confirmation.
I quoted badly; I believe there was a misunderstanding. The first quote in the parent to this should be taken in the context of your sentence segment that “Said literature gives advice”. In my paragraph, I was objecting to this from my experiences in my course, where I did not receive any advice on what to do in games like PD. Instead, the type of advice that I received was on how to calculate Nash equilibria and find SPNEs.
Otherwise, I am mostly in agreement with the latter part of that sentence. (ETA: That is, I agree that if current game theoretic equilibrium solutions are taken as advice on what one ought to do, then that is often epistemically, instrumentally, and normatively bad.)
More ETA:
You are correct – VNM-rationality is incredibly weak (though humans don’t satisfy it). It is, after all, logically equivalent to the existence of a utility function (the proof of this by von Neumann and Morgenstern led to the eponymous VNM theorem). The faux-rationality on LW and in popular culture requires much stronger assumptions. But again, I don’t think these assumptions are made in the game theory literature – I think that faux-rationality is misattributed to game theory. The game theory I was taught used only VNM-rationality, and gave no advice.