What is this post?

This post is a companion piece to recent posts on evidential cooperation in large worlds (ECL). We’ve noticed that in conversations about ECL, the same few initial confusions and objections tend to be brought up. We hope that this post will be useful as the place that lists and discusses these common objections. We invite the reader to advance additional questions and objections of their own.

This FAQ does not need to be read in order. The reader is encouraged to look through the section headings and jump to those they find most interesting.

ECL seems very weird. Are you sure you haven’t, like, taken a wrong turn somewhere?

We don’t think so.

ECL, at its core, takes two reasonable ideas that by themselves are considered quite plausible by many—albeit not completely uncontroversial—and notices that when you combine them, you get something quite interesting [...]

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Outline:

(00:06) What is this post?

(00:43) ECL seems very weird. Are you sure you haven’t, like, taken a wrong turn somewhere?

(01:43) Do I need to buy evidential decision theory for this to work?

(04:19) Okay, I see the intuitive appeal of cooperating in the near twin prisoners’ dilemma, but I am still skeptical of noncausal decision theories. Is there any theoretical reason to take noncausal decision theories seriously?

(06:19) Why aincha rich?

(07:01) CDT is exploitable.

(08:03) CDT offers counterintuitive advice.

(10:38) EDT, medical Newcomb problems and the tickle defense.

(12:45) Okay, so maybe I am not 100% confident in causal decision theory, but I am also not fully convinced by noncausal decision theory. What now?

(13:46) Is this a Pascal's mugging?

(16:43) Should we be clueless about our acausal effects?

(18:47) Does infinite ethics mess with ECL?

(21:06) Is ECL the same thing as acausal trade?

(21:41) Is ECL basically a multiverse-wide moral trade?

(23:00) Okay, I’ll grant that your toy setups work. But in the real world, we don’t have two neat actions with one labeled “cooperate.” We have lots of different available actions and compromise points. How is that supposed to work?

(25:22) You keep talking about “agents” for us to “do ECL” with… Who exactly are these agents?

(28:43) Is ECL action-relevant? Time-sensitive?

(31:02) How big a deal are the implications of ECL? How much does it change the impact of my actions?

(34:21) Acknowledgements

The original text contained 21 footnotes which were omitted from this narration.

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First published:
February 28th, 2024

Source:
https://www.lesswrong.com/posts/KCKxCQyvim9uNAnSC/evidential-cooperation-in-large-worlds-potential-objections

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Narrated by TYPE III AUDIO.

“Evidential cooperation in large worlds: Potential objections and FAQ” by Chi Nguyen

LessWrong (30+ Karma)