Note that there's some discussion on just what Eliezer means by "logic all the way down" over on Rationally Speaking: http://rationallyspeaking.blogspot.co.uk/2013/01/lesswrong-on-morality-and-logic.html . Seeing as much of this is me and Angra Maiynu arguing that Massimo Pigliucci hasn't understood what Eliezer means, it might be useful for Eliezer to confirm what he does mean.

arguing endlessly about definitions, or using one's own intuitions as strong evidence about how the external world works.

So this comes down to what you said previously about not liking people who came out of Philosophy 101, e.g., it's an argument against a philosophical tradition that does not actually exist.

These are bad habits relative to, you know, not arguing endlessly about definitions, and using science to figure out how the world works.

You mention naturalism as a "bad habit" for using science to understand the world?

Do you actually understand what naturalism is and what relationship it has with science?

This is a great post. I think the presentation of the ideas is clearer and more engaging than the sequences, and the cartoons are really nice. Wild applause for the artist.

I have a few things to say about the status of these ideas in mainstream philosophy, since I'm somewhat familiar with the mainstream literature (although admittedly it's not the area of my expertise). I'll split up my individual points into separate comments.

Alfred Tarski is a famous mathematician whose theory of truth is widely known.

Summary of my point: Tarski's biconditionals are not supposed to be a definition of truth. They are supposed to be a test of the adequacy of a proposed definition of truth. Proponents of many different theories claim that their theory passes this test of adequacy, so to identify Tarski's criterion with the correspondence theory is incorrect, or at the very least, a highly controversial claim that requires defense. What follows is a detailed account of why the biconditionals can't be an adequate definition of truth, and of what Tarski's actual theory of truth is.

Describing Tarski's biconditionals as a definition of truth or a theory of truth is misleading. The relevant paper is The Semantic Conception of Truth. Let's call sentences of the form 'p' is true iff p T-sentences. Tarski's claim in the paper is that the T-sentences constitute a criterion of adequacy for any proposed theory of truth. Specifically, a theory of truth is only adequate if all the T-sentences follow from it. This basically amounts to the claim that any adequate theory of truth must get the extension of the truth-predicate right -- it must assign the truth-predicate to all and only those sentences that are in fact true.

I admit that the conjunction of all the T-sentences does in fact satisfy this criterion of adequacy. All the individual T-sentences do follow from this conjunction (assuming we've solved the subtle problem of dealing with infinitely long sentences). So if we are measuring by this criterion alone, I guess this conjunction would qualify as an adequate theory of truth. But there are other plausible criteria according to which it is inadequate. First, it's a frickin' infinite conjunction. We usually prefer our definitions to be shorter. More significantly, we usually demand more than mere extensional adequacy from our definitions. We also demand intensional adequacy.

If you ask someone for a definition of "Emperor of Rome" and she responds "X is an Emperor of Rome iff X is one of these..." and then proceeds to list every actual Emperor of Rome, I suspect you would find this definition inadequate. There are possible worlds in which Julius Caesar was an Emperor of Rome, even though he wasn't in the actual world. If your friend is right, then those worlds are ruled out by definition. Surely that's not satisfactory. The definition is extensionally adequate but not intensionally adequate. The T-sentence criterion only tests for extensional adequacy of a definition. It is satisfied by any theory that assigns the correct truth predicates in our world, whether or not that theory limns the account of truth in a way that is adequate for other possible worlds. Remember, the biconditionals here are material, not subjunctive. The T-sentences don't tell us that an adequate theory would assign "Snow is green" as true if snow were green. But surely we want an adequate theory to do just that. If you regard the T-sentences themselves as the definition of truth, all that the definition gives us is a scheme for determining which truth ascriptions are true and false in our world. It tells us nothing about how to make these determinations in other possible worlds.

To make the problem more explicit, suppose I speak a language in which the sentence "Snow is white" means that grass is green. It will still be true that, for my language, "Snow is white" is true iff snow is white. Yet we don't want to say this biconditional captures what it means for "Snow is white" to be true in my language. After all, in a possible world where snow remained white but grass was red, the sentence would be false.

Tarski was a smart guy, and I'm pretty sure he realized all this (or at least some of it). He constantly refers to the T-sentences as material criteria of adequacy for a definition of truth. He says (speaking about the T-sentences), "... we shall call a definition of truth 'adequate' if all these equivalences follow from it." (although this seems to ignore the fact that there are other important criteria of adequacy) When discussing a particular objection to his view late in the paper, he says, "The author of this objection mistakenly regards scheme (T)... as a definition of truth." Unfortunately, he also says stuff that might lead one to think he does think of the conjunction of all T-sentences as a definition: "We can only say that every equivalence of the form (T)... may be considered a partial definition of truth, which explains wherein the truth of this one individual sentence consists. The general definition has to be, in a certain sense, a logical conjunction of all these partial definitions."

I read the "in a certain sense" there as a subtle concession that we will need more than just a conjunction of the T-sentences for an adequate definition of truth. As support for my reading, I appeal to the fact that Tarski explicitly offers a definition of truth in his paper (in section 11), one that is more than just a conjunction of T-sentences. He defines truth in terms of satisfaction, which in turn is defined recursively using rules like: The objects a and b satisfy the sentential function "P(x, y) or Q(x, y)" iff they satisfy at least one of the functions "P(x, y)" or "Q(x, y)". His definition of truth is basically that a sentence is true iff it is satisfied by all objects and false otherwise. This works because a sentence, unlike a general sentential function, has no free variables to which objects can be bound.

This definition is clearly distinct from the logical conjunction of all T-sentences. Tarski claims it entails all the T-sentences, and therefore satisfies his criterion of adequacy. Now, I think Tarski's actual definition of truth isn't all that helpful. He defines truth in terms of satisfaction, but satisfaction is hardly a more perspicuous concept. True, he provides a recursive procedure for determining satisfaction, but this only tells us when compound sentential functions are satisfied once we know when simple ones are satisfied. His account doesn't explain what it means for a simple sentential function to be satisfied by an object. This is just left as a primitive in the theory. So, yeah, Tarski's actual theory of truth kind of sucks.

His criterion of adequacy, though, has been very influential. But it is not a theory of truth, and that is not the way it is treated by philosophers. It is used as a test of adequacy, and proponents of most theories of truth (not just the correspondence theory) claim that their theory satisfies this test. So to identify Tarski's definition/criterion/whatever with the correspondence theory misrepresents the state of play. There are, incidentally, a group of philosophers who do take the T-sentences to be a full definition of truth, or at least to be all that we can say about truth. But these are not correspondence theorists. They are deflationists.

Don't be the guy who asks everyone in turn: the women talk to each other

This has mostly frightened me off so far. I've been tentatively pushing at it the last couple weeks.

1. You have to put yourself in environments where you'll be able to interact with a lot of women. College is in a lot of ways set up perfectly for this: if you're not in college right now, consider joining a class or an activity group. Try to make it one where the gender balance will be in your favor. Book groups are one example--they're wildly tilted towards women (I suspect men just, you know, read books, and don't tend to see the value in sitting around sipping coffee and talking about reading books). But if you like girls who wear glasses, try finding a congenial book group. You'll probably be the only man.

   Even better than book groups, though, are dance classes. Swing and rockabilly aren't super trendy anymore, but the scenes still exist in a quieter way, and these classes are great for single men: a) they're filled mostly with women; b) dance is an inherently flirtatious activity, and the physical leading/following dynamic is one that many women find very sexy; c) even if you don't find a date in that class, you'll have learned an attractive skill, and you'll be able to participate in events that will introduce you to more women; and d) physical exercise is good for building both confidence and sexiness. Yoga classes might work too, or if you can find a martial arts practice that attracts significant numbers of women (maybe check out your local aikido classes?).

   The SCA (Society for Creative Anachronism) is also a surprisingly good choice for geeks who want to hook up. Wearing princess dresses is enough of a draw for women that the gender balance, while tilted towards men, isn't too awful, and so many relationships get started in the context of SCA events that there's a joke about it. (The joke is that "SCA" actually stands for "Society for Consenting Adults.")

   There are of course singles bars or activities like speed-dating that are specifically designed to let you meet single women, so you could try those too. A lot of people find those environments stressful and frustrating, which is why I'd suggest finding a social scene that is not specifically about dating.

   Lastly, let all your friends know that you're interested in meeting women. Ask to be introduced to their friends who are single. This is how people used to meet each other and it is still an important avenue to keep open.

2. You have to ask women out on dates. This part, I know, is hard, and I'm sorry to admit that many women don't even understand how hard it is. You will be rejected and it will suck every time, but this part is a numbers game. You just have to keep doing it until you find the girl who says "yes."

   The pre-reqs for asking a girl out are fewer than you might think. It's best if you have already been introduced and have interacted a bit in a friendly manner. When I say a bit, I really mean just that you've spoken a few times. It is far, far more common for geek guys to err wildly in the opposite direction. Don't do this. If you like her, ask her out, and make your intentions unambiguous. The sooner the better.

   If you're following my advice and meeting girls in activity classes, you would do this by approaching her just after one of the classes, maybe as she's getting her things together or as she's heading out the door. Make eye contact and smile. Start with a compliment that references the interactions you've had--"Hey, I've really been enjoying dancing with you [or "sparring with you," or, "I really liked what you said about the book"] and I wonder if I could take you out to a movie next week."

   Be really clear about the fact that you're asking her for a date. Try not to say something like "I wonder if you'd like to meet for coffee and talk " because she could interpret this as merely a friendly gesture on your part, and you don't want that. A lot of inexperienced guys think they should establish a friendship before they ask a girl out, but you really don't want to sink a lot of time and energy into a girl who is never going to see you "like that." (It is true that established friendships can make a wonderful basis for romance, but never, ever count on that happening.)

   Also, propose a specific activity and a specific time. Don't just say "I wonder if you'd go out with me some time" because a) it sounds a little desperate and b) a lot of women have trouble saying "no" directly (we're socialized not to). Leave her a face-saving way to refuse. If she says "I'd love to but I've been really busy with work/school/life recently," that means no. Move on. (If, on the other hand, she says "I'm going to Guatemala next week, but I'll be back by the end of the month, maybe then?" that means yes.)

Dealing with rejection: When you are rejected, try to be gracious about it, even if she is not. Like I said above, a lot of women truly do not understand how much gumption it takes to put yourself out there by making a pass. If she seems annoyed or condescending or whatever, try to shrug it off; just smile and say "okay, no problem" or something along those lines. Do the same thing if she says "I'd rather just be friends." (But for the love of Pete, do not spend a lot of effort trying to actually cultivate a friendship. Moooooove on.)

It does get easier the more you do it. Just remind yourself that it is a numbers game. The worst thing that can happen is not that you ask ten girls out and they all say no. The worst thing is that you ask ten girls, they say no, and then you stop asking. Because whether it was Girl #11 or Girl #83 who would've fallen head over heels for you, you'll never find her now. Keep looking to meet women, and keep asking them out; these are the two steps that lead to relationships.

Troubleshooting: If you do find that you are consistently rejected, there might be something going on with your self-presentation that is offputting to women. Make sure your basic hygiene is good: that you are wearing clean clothes that fit you, that your hair is cut and that you are clean-shaven. (Facial hair is Advanced Fashion for Men: if fashion is not your ballgame, just shave, trust me.) Ask your friends if there's anything going on with your looks or demeanor that might be getting in your way.

If you are overweight, start an exercise regimen, but do not wait until you are at your ideal weight to start asking women on dates. It is perfectly possible for big dudes to find love, they do it all the time. It IS more important to make sure that you wear flattering clothing that fits you well--a baggy, threadbare tee-shirt and Hawaiian shorts may not cut it. Use Google Images to find pictures of some of the heavier celebrities (like Sean Astin, or Seth Rogan before he slimmed down). Check out what they are/were wearing, and use those pictures as a style guide.

You may also be acting in ways that indicate you don't value yourself, which can make women (and other people in general) instinctively shy away. You will probably need the help of people who actually know you to diagnose these kinds of problems and help you fix them.

In general, though, from my observations, most geek guys are able to get dates so long as they go where the women are, and ask them out. The most common mistake by far is simply failing to execute one or both of these crucial steps.

I think I'm free. The same time the following weekend is bad for me, but Sunday 20th is OK.

which I'm pretty sure I first found here, HT

Glad you liked it.

Suber seems to concentrate on tactics where one person avoids responding to the argument by making some statement about the arguer ("you're saying that because of your hopeless confirmation bias!") That sort of rudeness is a potential problem if someone has a belief which includes explanations of why other people don't believe it. I'm not sure what to do to about that, since I certainly have such beliefs. As far as I can make out, if I want to avoid being rude, I end up having to respond to arguments against my belief even though I think those arguments aren't reason the arguer doesn't share my belief.

Your example of people who concede Y but then switch to Z reminds me of When Theism is Like an M.C. Escher Drawing.

[edit: remove spurious "aren't']

The whole interview the quote came from is worth reading.

Especially since it contradicts what you just said about Brown not doing NLP. From the interview:

Well, I not a big a fan of it, but I've done it and think in some contexts there's some use.... It's not what I do. It's part of what I do."

It struck me that the interviewer was really pressing Brown rather hard to say that things like NLP and hypnosis are shams and false, and Brown was pressing back rather hard with the idea that no, people can actually get some benefits from learning these things, they just won't be able to duplicate all my effects that way.

Of course, I've seen Brown do certain things that are pretty much straight-up, textbook NLP or hypnosis with no real embellishing. For example, confusing a woman about what color her car is - a simple submodality anchoring belief-change exercise, straight out of the NLP textbooks, with no alterations that I noticed.

And the one where he uses blank pieces of paper to pay for things as if it were money, he uses an NLP language pattern to prime the person at a critical moment with the idea that "it's good; take it". (Although I suppose you could say it's an Ericksonian hypnosis pattern; the NLP inventors certainly were among the first to document it, however.)

That having been said, quite a few things he does are not NLP at all, or at least not any cataloged NLP technique I know of.

The bit at the end of the trick where he gleefully shows you how he did it using NLP to implant words in people's minds is itself misdirection.

In neither of the two cases that I just mention, did Brown draw any attention to the NLP aspect of the effects, either verbally or nonverbally. He provided no explanation at all for either, actually. (Maybe he only does it with techniques that aren't real NLP?)

Anyway, I had to very carefully view the paying-with-paper footage several times in order to notice what he was doing, as he was telling different stories each time in which to embed the "it's good, take it" message, which was always timed to occur just as he was handing them the "money".

(Of course, I also respect him for including outtake footage in the episode of him trying the trick on a suspicious hotdog vendor (whose English wasn't so good) and having it fail miserably. I'm glad he's not representing these things as working every time on everybody without fail.)

But is PUA discussed here because it's a great example of evolutionary psychology in practise, or because this is a community of mostly single men who are interested in evolutionary psychology? I find neuro-linguistic programming endlessly fascinating and would love to see a good article on it at Less Wrong, but what are the odds that it will reference* pickup artists rather than, say, Derren Brown?

*The odds that no pop cultural references will be made are low. This is Less Wrong.

Cambridge, UK.