Aubrey de Grey Discussion, 14

I discussed epistemology and cryonics with Aubrey de Grey via email. Click here to find the rest of the discussion. Yellow quotes are from Aubrey de Grey, with permission. Bluegreen is me, red is other.

If all you do is partial CR and have two non-refuted options, then they have equal status and should be given equal probability.

When you talk about amounts of sureness, you are introducing something that is neither CR nor dice rolling.

I think you answer this with this:

A reason "strong refutation" seems to make sense is because of something else. Often what we care about is a set of similar ideas, not a single idea. A refutation can binary refute some ideas in a set, and not others. In other words: criticisms that refute many variants of an idea along with it seem "strong”.

That’s basically what I do. I agree with all you go on to say about closeness of variants etc, but I see exploration of variants (and choice of how much to explore variants) as coming down to a sequence of dice-rolls (or, well, coin-flips, since we’re discussing binary choices).

I don't know what this means. I don't think you mean you judge which variants are true, individually, by coin flip.

Maybe the context is only variants you don't have a criticism of. But if several won their coin flips, but are incompatible, then what? So I'm not clear on what you're saying to do.


Also, are you saying that amount of sureness, or claims criticisms are strong or weak (you quote me explaining how what matters is which set of ideas a criticism does or doesn't refute), play no role in what you do? Only CR + randomness?

Also, if you felt 95% sure that X was a better approach than Y – perhaps a lot better – would you really want to roll dice and risk having to do Y, against your better judgment? That doesn't make sense to me.

It makes sense if we remember that the choice I’m actually talking about is not between X and Y, but between X, Y and continuing to ruminate. If I’ve decided to stop ruminating because X feels sufficiently far ahead of Y in the wiseness stakes, then I could just have a policy of always going with X, but I could equally step back and acknowledge that curtailing the rumination constitutes dice-rolling by proxy and just go ahead and do the actual dice-roll so as to feel more honest about my process. I think that makes fine sense.

I think you're talking about rolling dice meaning taking risks in life - which I have no objection to. Whereas I was talking about rolling dice specifically as a decision making procedure for making choices. And that was in context of making an argument which may not be worth looking up at this point, but there you have a clarification if you want.

To try to get at one of the important issues, when and why would you assign X a higher percent (aka strength, plausibility, justification, etc) than Y or than ruminating more? Why would the percents ever be unequal? I say either you have a criticism of an option (so don't do that option), or you don't (so don't raise or lower any percents from neutral). What specifically is it that you think lets you usefully and correctly raise and lower percents for ideas in your decision making process?

I think your answer is you judge positive arguments (and criticisms) in a non-binary way by how "solid" arguments are. These solidity judgments are made arbitrarily, and combined into an overall score arbitrarily. Your defense of arbitrariness, rather than clearly explained methods, is that better isn't possible. If that's right, can you indicate specifically what aspects of CR you consider sometimes impossible, in what kinds of situations, and why it's impossible?

(Most of the time you used the word "subjective" rather than "arbitrary". If you think there's some big difference, please explain. What I see is a clear departure from objectivity, rationality and CR.)

The ways to deal with fallibilism

Do you mean something different here than “fallibility”?

I meant fallibilism, but now that you point it out I agree "fallibility" is a clearer word choice.

are doing your best with your current knowledge (nothing special), and also specifically having methods of thinking which are designed to be very good at finding and correcting mistakes.

Sure - and that’s what I claim I do (and also what I claim you in fact do, even though you don’t think you do).

I do claim to do this. Do you think it's somehow incompatible with CR?

I do have some different ideas than you about what it entails. E.g. I think that it never entails acting on a refuted idea (refuted in the actor's current understanding). And never entails acting on one idea over another merely because of an arbitrary feeling that that idea is better.

You've acknowledged your approach having some flaws, but think it's good enough anyway. That seems contrary to the spirit of mistake correction, which works best when every mistake found is taken very seriously.

Oh no, not at all - my engagement in this discussion is precisely to test my belief that my approach is good enough.

Yes, but you're arguing for the acceptance of those flaws as good enough.

I realize you also think something like one can't do better (so they aren't really flaws since better isn't achievable). That's a dangerous kind of claim though, and also important enough that if it was true and well understood, then there ought be books and papers explaining it to everyone's satisfaction and addressing all the counter-arguments. (But those books and papers do not exist.)

Not really, because hardly anyone thinks what you think. If CR were a widely-held position, there would indeed be such books and papers, but as far as I understand it CR is held only by you, Deutsch and Popper (I restrict myself, of course, to people who have written anything on the topic for public consumption), and Popper’s adherence to it is not widely recognised. Am I wrong about that?

I think wrong. Popper is widely recognized as advocating CR, a term he coined. And there are other Critical Rationalists, for example:

http://www.amazon.com/Critical-Rationalism-Metaphysics-Science-Philosophy/dp/0792329600

This two volume CR book has essays by maybe 40 people.

CR is fairly well known among scientists. Example friendly familiar people include Feynman, Wheeler, Einstein, Medawar.

And there's other people like Alan Forrester ( http://conjecturesandrefutations.com ).

I in no way think that ideas should get hearings according to how many famous or academic people think they deserve hearings. But CR would pass that test.


I wonder if you're being thrown off because what I'm discussing includes some refinements to CR? If the replies to CR addressed it as Popper originally wrote it, that would be understandable.

But there are no quality criticisms of unmodified-CR (except by its advocates who wish to refine it). There's a total lack of any reasonable literature addressing Popper's epistemology by his opponents, and meanwhile people carry on with ideas contradicting what Popper explained.

I wonder also if you're overestimating the differences between unmodified CR and what I've been explaining. They're tiny if you use the differences between CR and Justificationism as a baseline. Like how the difference between Mac and Windows is tiny compared to the difference between a computer and a lightbulb.


Even if Popper didn't exist, any known flaws to be accepted with Justificationism ought to be carefully documented by people in the field. They should write clear explanations about why they think better is impossible in those cases, and why not to do research trying for better since it's bound to fail in ways they already understand, and the precise limits for what we're stuck with, and how to mitigate the problems. I don't think anything good along these lines exists either.

Since we agreed some time ago that mathematical proofs are a field in which pure CR has a particularly good chance of being useful,

I consider CR equally useful in all fields. Substitute "CR" for "reason" in these sentences – which is my perspective – and you may see why.

Sorry, misunderstanding - what I meant was “Since mathematical proofs are a field in which I have less of a problem with a pure CR approach than with most fields, because expert consensus nearly always turns out to be rather rapidly achieved”

I don't think lack of expert consensus in a field is problematic for CR or somehow reduces the CR purity available to an individual.

There are lots of reasons expert consensus isn't reached. Because they don't use CR. Because they are more interested in promotions and reputation than truth. Because they're irrational. Because they are judging the situation with different evidence and ideas, and it's not worth the transaction costs to share everything so they can agree, since there's no pressing need for them to agree.

What's the problem for CR with consensus-low fields?

This is a general CR approach: do something with no proof it will work, no solidity, no feeling of confidence (or if you do feel confidence, it doesn't matter, ignore it). Instead, watch out for problems, and deal with them as they are found.

Again, I can’t discern any difference in practice between that and what I already do.

Can you discern a difference between it and what most people do or say they do?

I don’t think our disparate conclusions with regard to the merits of signing up with Alcor arise from you doing the above and me doing something different; I think they arise from our having different criteria for what constitutes a problem. And I don’t think this method allows a determination of which criterion for what constitutes a problem is correct, because each justifies itself: by your criteria, your criteria are correct, and by mine, mine are. (I mentioned this bistability before; I’ve gone back to your answer - Sept 27 - and I don’t understand why it’s an answer.)

Criteria for what is a problem are themselves ideas which can be critically discussed.

Self-justifying ideas which block criticism from all routes are a general category of idea which can be (easily) criticized. They're bad because they block critical discussion, progress, and the possibility of correction if they're mistaken.

And here is a different answer: You cannot mitigate all the infinite risks that are logically possible. You can't do anything about the "anything is possible" risk, or the general risks inherent in fallibility. What you can do is think of specific categories of risks, and methods to mitigate those categories. Then because you're dealing with a known risk category, and known mitigation methods – not the infinite unknown – you can have some understanding of how big the downsides involved are and the effectiveness of time spent on mitigation. Then, considering other things you could work on, you can make resource allocation decisions.

Same answer - I maintain that that’s what I already do.

Do you maintain that what I've described is somehow not pure CR? The context I was addressing included e.g.:

It seems to me that the existence of cases where people can be wrong for a long time constitutes a very powerful refutation of the practicality of pure CR, since it means one cannot refute the argument that there is a refutation one hasn’t yet thought of.

You were presenting a criticism of CR, and when I talked about how to handle the issues, you've now said stuff along the lines of that's what you already do, indicating some agreement. Are you then withdrawing that criticism of CR? If so, do you think it's just you specifically who does CR (for this particular issue), or most people?

Or more precisely, the issue isn't really whether people do CR - everyone does. It's whether they *say* they do CR, whether they understand what they are doing, and whether they do it badly due to epistemological confusion.

Continue reading the next part of the discussion.