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Comment author: JonathanLivengood 06 May 2013 04:49:04AM 4 points [-]

If the AI actually ends up with strong evidence for a scenario it assigned super-exponential improbability, the AI reconsiders its priors and the apparent strength of evidence rather than executing a blind Bayesian update, though this part is formally a tad underspecified.

I would love to have a conversation about this. Is the "tad" here hyperbole or do you actually have something mostly worked out that you just don't want to post? On a first reading (and admittedly without much serious thought -- it's been a long day), it seems to me that this is where the real heavy lifting has to be done. I'm always worried that I'm missing something, but I don't see how to evaluate the proposal without knowing how the super-updates are carried out.

Really interesting, though.

Comment author: RobbBB 02 May 2013 06:14:16AM *  2 points [-]

Jonathan, Anti-Realism here isn't restricted to the view in philosophy of science. It's also associated with a rejection of the correspondence and deflationary theories of truth and of external-world realism. I'm currently somewhere in between a scientific realist and a structural realist, and I'm fine with classifying the latter as an anti-realism, though not necessarily in the sense of Anti-Realism Chalmers coined above to label one of the factors.

Your characterization of scientific realism, though, is way too strong. "In every case" should read "In most cases" or "In many cases", for Epistemic Realism. That's already a difficult enough view to defend, without loading it with untenable absolutism.

My main concern with Anti-Realists isn't that they're often skeptical about whether bosons exist; it's that they're often skeptical about whether tables exist, and/or about whether they're mind-independent, and/or about whether our statements about them are true in virtue of how the world outside ourselves is.

Comment author: JonathanLivengood 02 May 2013 06:50:16AM 2 points [-]

Ah, I see that I misread. Somehow I had it in my head that you were talking about the question on the philpapers survey specifically about scientific realism. Probably because I've been teaching the realism debate in my philosophy of science course the last couple of weeks.

I am, however, going to disagree that I've given a too strong characterization of scientific realism. I did (stupidly and accidentally) drop the phrase "... is true or approximately true" from the end of the second commitment, but with that in place, the scientific realist really is committed to our being able to uniquely determine by evidence which of several literal rivals we ought to believe to be true or approximately true. Weakening to "most cases" or "many cases" deflates scientific realism significantly. Even constructive empiricists are going to believe that many scientific theories are literally true, since many scientific theories do not say anything about unobservable entities.

Also, without the "in every case," it is really hard to make sense of the concern realists have about under-determination. If realists thought that sometimes they wouldn't have good reasons to believe some one theory to be true or approximately true, then they could reply to real-life under-determination arguments (as opposed to the toy examples sometimes offered) by saying, "Oh, this is an exceptional case."

Anyway, the kinds of anti-realist who oppose scientific realism almost never deny that tables exist. (Though maybe they should for reasons coming out of material object metaphysics.)

Comment author: Desrtopa 01 May 2013 11:01:06PM 0 points [-]

I would be interested in seeing how philosophers do on tests of analytical versus intuitive reasoning (I forget the name of the test normally used for gauging this) and ability to narrow down hypotheses when the answers are known and easily verifiable.

Comment author: JonathanLivengood 02 May 2013 06:07:18AM 2 points [-]

We do pretty well, actually (pdf). (Though I think this is a selection effect, not a positive effect of training.)

Comment author: RobbBB 01 May 2013 04:26:58PM *  3 points [-]

I'd say the Anti-Naturalism and Anti-Realism clusters are obviously wrong. Trekophobia and Logical Conventionalism are less obvious, though they clearly go against a lot of the basic views and tendencies on LW. Objectivism and Rationalism are more debatable, and Externalism seems the most LWy on a cursory look. But even Externalism only gets a couple of things consistently right, at best. (And in a fairly arbitrary manner.)

Perhaps I under-emphasized a really crucial point: All of these clusters should be criticized not just for the views you see, but for the ones you don't see. Why don't Externalists knock physicalism out of the ballpark? Why aren't Rationalists winning at Newcomb's Problem 80, 90, 100% of the time? Defensibility is an indefensibly low standard; expecting mediocrity is expecting too little even of high school philospohy students, to say nothing of those who have devoted 30, 40, 50 years to grasping these topics, with all the resources of human civilization at their disposal.

Too slow.

Comment author: JonathanLivengood 02 May 2013 05:59:16AM 2 points [-]

I'm guessing that you don't really know what anti-realism in philosophy of science looks like. I suspect that most of the non-specialist philosophers who responded also don't really know what the issues are, so this is hardly a knock against you. Scientific realism sounds like it should be right. But the issue is more complicated, I think.

Scientific realists commit to at least the following two theses:

(1) Semantic Realism. Read scientific theories literally. If one theory says that space-time is curved and there are no forces, while the other says that space-time is flat and there are primitive forces (so the two have exactly the same observational consequences in all cases), then the realist says that at most one of the two is true.

(2) Epistemic Realism. In every case, observation and experimentation can provide us with good epistemic (as opposed to pragmatic) reasons to believe that what some single theory, read literally, says about the world.

Denying either of these leads to some form of anti-realism, broadly construed. Positivists, instrumentalists, and pragmatists deny (1), as Einstein seems to have done in at least two cases. Constructive empiricists deny (2) in order to keep a commitment to (1) while avoiding inflationary metaphysics. Structural realists deny one or both of these commitments, meaning that they are anti-realists in the sense of the question at stake.

Comment author: Manfred 10 April 2013 05:53:43PM 0 points [-]

Oh, sorry, by "we" I meant the constituent people, not the group.

Comment author: JonathanLivengood 10 April 2013 07:38:33PM 0 points [-]

Ah, gotcha.

Comment author: Manfred 10 April 2013 04:11:59PM *  0 points [-]

Yeah, we're still here, but it's sort of like a DnD group, if you have too many "no-go" sessions, people stop bothering.

Though on the other hand, I kinda want to do paranoid debating now.

Comment author: JonathanLivengood 10 April 2013 05:09:30PM 0 points [-]

Are the meetings word of mouth at this point, then? When is the next meeting planned?

Comment author: JonathanLivengood 10 April 2013 03:46:56PM 0 points [-]

I have had some interest, but I never managed to attend any of the previous meetups. I don't know if I will find time for it in the future.

Comment author: IlyaShpitser 06 January 2013 12:52:56PM 1 point [-]

I agree that Hume was not thinking coherently about causality, but the credit for the counterfactual definition still ought to go to him, imo. Are you aware of an earlier attempt along these lines?

Comment author: JonathanLivengood 06 January 2013 01:56:42PM 0 points [-]

That question raises a bunch of interpretive difficulties. You will find the expression sine qua non, which literally means "without which not," in some medieval writings about causation. For example, Aquinas rejects mere sine qua non causality as an adequate account of how the sacraments effect grace. In legal contexts today, that same expression denotes a simple counterfactual test for causation -- the "but for" test. One might try to interpret the phrase as meaning "indispensable" when Aquinas and other medievals use it and then deflate "indispensable" of its counterfactual content. However, if "indispensable" is supposed to lack counterfactual significance, then the same non-counterfactual reading could, I think, be taken with respect to that passage in Hume. I don't know if the idea shows up earlier. I wouldn't be surprised to find that it does.

Comment author: Peterdjones 05 January 2013 06:10:15PM *  -1 points [-]

I do claim that almost all philosophy is useless for figuring out what is true,

I'll say it again: there is no point in criticising philosophy unless you have (1) a better way of (2) answering the same questions.


Mark doesn't explain here why it's "nonsense" to propose that truth-seekers (qua truth-seekers) should ignore 99% of all philosophy,

See above. You need something better.

why many metaphysical arguments aren't meaningless

LP is a known failure, as has been pointed out here innumberable times The burden is on you to justify the LP metaphsics-is-nonsense principle.

, why some philosophical problems can't simply be dissolved,

Mark doesn't have to arge that no problem can be dissolved, since he never claimed that. You probably need to arge that the majority can be dissolved , since you keep citing the proportion of philosophy that is worthless as over 90%. You also probably need to expaln why phils. can't do that, in the teeth of examples of the doing just that (eg Dennett on quaia).

nor why Chalmers' approach to philosophy is superior to Eliezer's.

Consider this: If an amaterur claims to be doing considerably better than an acknowledged domain expert, he is probably suffering from the Dunning-Krueger effect.

Comment author: JonathanLivengood 06 January 2013 10:36:24AM 5 points [-]

I'll say it again: there is no point in criticising philosophy unless you have (1) a better way of (2) answering the same questions.

Criticism could come in the form of showing that the questions shouldn't be asked for one reason or another. Or criticism could come in the form of showing that the questions cannot be answered with the available tools. For example, if I ran into a bunch of people trying to trisect an arbitrary angle using compass and straight-edge, I might show them that their tools are inadequate for the task. In principle, I could do that without having any replacement procedure. And yet, it seems that I have helped them out.

Such criticism would have at least the following point. If people are engaged in a practice that cannot accomplish what they aim to accomplish, then they are wasting resources. Getting them to redirect their energies to other projects -- perhaps getting them to search for other ways to satisfy their original aims (ways that might possibly work) -- would put their resources to work.

Comment author: IlyaShpitser 06 January 2013 08:58:30AM 1 point [-]

Hume was the first to come up with a counterfactual definition of causality, I think.

Comment author: JonathanLivengood 06 January 2013 10:18:20AM 1 point [-]

That is being generous to Hume, I think. The counterfactual account in Hume is an afterthought to the first of his two (incompatible) definitions of causation in the Enquiry:

Similar objects are always conjoined with similar. Of this we have experience. Suitably to this experience, therefore, we may define a cause to be an object, followed by another, and where all the objects similar to the first are followed by objects similar to the second. Or in other words where, if the first object had not been, the second never had existed.

As far as I know, this is the only place where Hume offers a counterfactual account of causation, and in doing so, he confuses a counterfactual account with a regularity account. Not promising. Many, many people have tried to find a coherent theory of causation in Hume's writings: he's a regularity theorist, he's a projectivist, he's a skeptical realist, he's a counterfactual theorist, he's an interventionist, he's an inferentialist ... or so various interpreters say. On and on. I think all these attempts at interpreting Hume have been failures. There is no Humean theory to find because Hume didn't offer a coherent account of causation.

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