gedymin

Karma: 192

gedymin 26 Mar 2015 8:58 UTC
0 points
in reply to: Bugmaster’s comment on: Why I Reject the Correspondence Theory of Truth

you end up observing the outputs of models, as suggested in the original post.

I agree with pragmatist (the OP) that this is a problem for the correspondence theory of truth.

What is it that makes their accumulated knowledge worthy of being relied upon ?

Usefulness? Just don’t say “experimental evidence”. Don’t oversimplify epistemic justification. There are many aspects—how well knowledge fits with existing models, with observations, what is it’s predictive power, what is it’s instrumental value (does it help to achieve one’s goals) etc. For example, we don’t have any experimental evidence that smoking causes cancer in humans, but we nevertheless believe that is does. The power of Bayesian approach is in the mechanism to fuse together all these different forms of evidence and to arrive at a single posterior probability.

gedymin 25 Mar 2015 22:18 UTC
0 points
in reply to: Bugmaster’s comment on: Why I Reject the Correspondence Theory of Truth

How do you evaluate whether any given model is useful of not?

One way is to simulate a perfect computational agent, assume perfect information, and see what kind of models it would construct.

If you reject the notion of an external reality that is accessible to us in at least some way, then you cannot really measure the performance of your models against any kind of a common standard.

Solomonoff induction provides a universal standard for “perfect” inductive inference, that is, learning from observations. It is not entirely parameter-free, so it’s “a standard”, not “the standard”. I doubt if there is the standard for the same reasons I doubt that Platonic Truth does exist.

All you’ve got left are your internal thoughts and feelings

Umm, no, this is a false dichotomy. There is a large area in between “relying on one’s intuition” and “relying on an objective external word”. For example, how about “relying on the accumulated knowledge of others”?

See also my comment in the other thread.

gedymin 24 Mar 2015 18:19 UTC
−1 points
on: Why I Reject the Correspondence Theory of Truth
I’ve got feeling that the implicit LessWrong’ish rationalist theory of truth is, in fact, some kind of epistemic (Bayesian) pragmatism, i.e. “true is that what is knowable using probability theory”. May also throw in ”..for a perfect computational agent”.

My speculation is that the declared LW’s sympathy towards the correspondence theory of truth stems from political / social reasons. We don’t want to be confused with the uncritically thinking masses—the apologists of homoeopathy or astrology justifying their views by “yeah, I don’t know how it works either, but it’s useful!”; the middle-school teachers who are ready to threat scientific results as epistemological equals of their favourite theories coming from folk-psychology, religious dogmas, or “common sense knowledge”, because, you known, “they all are true in some sense”. Pragmatic theories of truth are dangerous if they come into the wrong hands.

gedymin 24 Mar 2015 18:01 UTC
1 point
in reply to: Vladimir_Nesov’s comment on: Why I Reject the Correspondence Theory of Truth

What do you mean by “direct access to the world”?

Are you familiar with Kant? http://en.wikipedia.org/wiki/Noumenon

gedymin 24 Mar 2015 12:46 UTC
0 points
in reply to: alienist’s comment on: Rationality Quotes Thread March 2015
This description fits philosophy much better than science.

gedymin 24 Mar 2015 12:29 UTC
0 points
on: What you know that ain’t so
Sounds like a form of abduction, or, more precisely, failure to consider alternative hypotheses.

gedymin 24 Mar 2015 10:53 UTC
8 points
on: Request for Steelman: Non-correspondence concepts of truth
As for your options, have you considered the possibility that 99% of people have never formulated a coherent philosophical view on the theory of truth?

gedymin 24 Mar 2015 10:32 UTC
0 points
on: Request for Steelman: Non-correspondence concepts of truth
I’d love to hear a more qualified academic philosopher discuss this, but I’ll try. It’s not that the other theories are intuitively appealing, it’s that the correspondence theory of truth has a number of problems, such as the problem of induction.

Let’s say the one day we create a complete simulation of a universe where the physics almost completely match ours, except some minor details, such as that some specific types of elementary particles, e.g. neutrinos are never allowed to appear. Suppose that there are scientists in the simulation, and they work out the Standard Model of their physics. The model presupposes existence of neutrinos, but their measurement devices are never going to interact with a neutrino. Is the statement “neutrinos exist” true or false from their point of view? I’d say that the answer is “does not matter”. To turn the example around, can we be sure that aether does not exist? Under Bayesianism, every instance of scientists not observing aether increases our confidence. However we might be living in a simulation where the simulators have restricted all observations that could reveal the existence of aether. So it cannot be completely excluded that aether exists, but is unobservable. So the correspondence theory is forced to admit that “aether exists” has an unknown truth value. In contrast, a pragmatic theory of truth can simply say that anything that cannot, in principle, be observed by any means also does not exist, and be fine with that.

Ultimately, the correspondence theory presupposes a deep Platonism as it relies on the Platonic notion of Truth being “somewhere out there”. It renders science vulnerable to problem of induction (which is not a real problem as far as real world is concerned) - it allows anyone to dismiss the scientific method off-handedly by saying that “yeah, but science cannot really arrive at the Truth—already David Hume proved so!”

We have somehow to deal with the possibility that everything we believe might turn out to be wrong (e.g. we are living in a simulation, and the real world has completely different laws of physics). Accepting correspondence theory means accepting that we are not capable of reaching truth, and that we are not even capable of knowing if we’re moving in the direction of truth! (As our observations might give misleading results.) A kind of philosophical paralysis, which is solved by the pragmatic theory of truth.

There’s also the problem that categories really do not exist in some strictly delineated sense; at least not in natural languages. For example consider the sentences in form “X is a horse”. According to correspondence, a sentence from this set is true iff X is a horse. That seems to imply that X must be a mammal of genus Equus etc. - something with flesh and bones. However, one can point to a picture of a horse and say “this is a horse”, and would not normally be considered lying. Wittgenstein’s concept of family resemblance comes to rescue, but I suspect does not play nicely with the correspondence theory.

Finally, there’s a problem with truth in formal systems. Some problems in some formal systems are known to be unsolvable; what is the truth value of statements that expand to such a problem? For example, consider the formula G (from Goedel’s incompleteness theorem) expressed in Peano Arithmetic. Intuitively, G is true. Formally, it is possible to prove that assuming G is true does not lead to inconsistencies. To do that, we can provide a model of Peano Arithmetic using this standard interpretation. The standard set of integers is an example of such a model. However, it is also possible to construct nonstandard models of Peano Arithmetic extended with negation of G as an axiom. So assuming that negation of G is true also does not lead to contradictions. So we’re back at the starting point—is G true? Goedel thought so, but he was a mathematical Platonist, and his views on this matter are largely discredited by now. Most do not believe that G has a truth value is some absolute sense.

This aspect together with Tarki’s undefinability theorem suggest that is might not make sense to talk about unified mathematical Truth. Of course, formal systems are not the same as the real world, but the difficulty of formalizing truth in the former increases my suspicion of formalizations / axiomatic explanations relevant to in the latter.
What links here?
- gedymin's comment on Why I Reject the Correspondence Theory of Truth by pragmatist (25 Mar 2015 22:18 UTC; 0 points)

gedymin 5 Mar 2015 9:08 UTC
5 points
in reply to: Vulture’s comment on: Stupid Questions March 2015
I meant that as a comment to this:

the information less useful than what you’d get by just asking a few questions.

It’s easy to lie when answering to questions about your personality on e.g. a dating site. It’s harder, more expensive, and sometimes impossible to lie via signaling, such as via appearance. So, even though information obtained by asking questions is likely to be much richer than information obtained from appearances, it is also less likely to be truthful.

gedymin 4 Mar 2015 16:40 UTC
0 points
in reply to: Strilanc’s comment on: Stupid Questions March 2015
..assuming the replies are truthful.

gedymin 4 Mar 2015 15:11 UTC
4 points
in reply to: [deleted]’s comment on: Open thread, Mar. 2 - Mar. 8, 2015
I think universalism is an obvious Schelling point. Not just moral philosophers find it appealing, ordinary people do it too (at least when thinking about it in an abstract sense). Consider Rawls’ “veil of ignorance”.

gedymin 4 Mar 2015 15:04 UTC
2 points
in reply to: [deleted]’s comment on: Open thread, Mar. 2 - Mar. 8, 2015
Mountaineering or similar extreme activities is one option.

gedymin 4 Mar 2015 14:58 UTC
4 points
on: Stupid Questions March 2015
Are there any moral implications of accepting the Many Worlds interpretation, and if so what could they be?

For example, if the divergent copies of people (including myself) in other branches of Multiverse should be given non-insignificant moral status, then it’s one more argument against the Epicurean principle that “as long as we exist, death is not here”. My many-worlds self can die partially—that is, just in some of the worlds. So I should to reduce the number of worlds in which I’m dead. On the other hand, does it really change anything compared to “I should reduce the probability that I’m dead in this world”?

gedymin 4 Mar 2015 14:43 UTC
7 points
on: Stupid Questions March 2015
Is there some reason to think that physiognomy really works? Reverse causation is probably the main reason, e.g. tall people are more likely to be seen as leaders by others, so they are more likely to become leaders. Nevertheless, is there something beyond that?

gedymin 3 Mar 2015 19:53 UTC
2 points
in reply to: [deleted]’s comment on: Towards a theory of nerds… who suffer.
Funny, I thought escaping in their own private world was not something exclusive to nerds. In fact most people do that. Schoolgirls escape in fantasies about romance. Boys in fantasies about porn. Gamers in virtual reality. Athletes in fantasies about becoming famous in sport. Mathletes—about being famous and successful scientists. Goths—musicians or artists. And so on.

True, not everyone likes to escape in sci-fi or fantasy, but that’s because different minds are attracted by different kinds of things. D&D is a relatively harmless fantasy. I’m not that familiar with it, so I’m not even sure whether it can be used to diagnose “nerds”, but that’s not the point. Correlation is not causation.

Regarding “jerks”, we apparently have disagreement on definitions, so this is an issue not worth pursuing. My point is that your self-styled definition of a “nerd” is bit ridiculous, as in fact you’re talking about three different groups of people that just happen to be overlapping.

gedymin 3 Mar 2015 13:28 UTC
2 points
on: Towards a theory of nerds… who suffer.
the solution will involve fixing things that made one a “tempting” bullying target

So a nerd, according to the OP, is someone who:
- lacks empathy and interest in other people
- lacks self confidence
- has unconventional interests, ideas, and appearance
But even if take for granted that this is a correct description of a nerd, these are very different issues and require very different solutions.

The last problem is simple to fix at the level of society and ought to be fixed there. A hate against specific social groups should not be acceptable, not matter how intuitive it feels, and how deep its biologically basis is. The current situation in which hate towards different races, nationalities, genders etc. is not politically acceptable, but the hate towards nerds is does not make sense. Overall, people have learned and mostly agree that tolerance is a good idea—but it is still applied very selectively. For example, if parents and schools are capable of avoiding race-hate in the classrooms (less or more), then they should be capable of censoring nerd-hate to an equal extent.

The problem of nerds being jerks and suffering as a consequence is not a real social problem at all. For a society as whole, it is giving negative feedback to someone being a jerk. It’s a regulatory mechanism. Here I agree with the OP that self-improvement is the action to take,

The problem of self-confidence is a real problem, as in this case it easily leads to a negative feedback loop. If the usual ways of increasing self-confidence do not help, I see no moral arguments against e.g. using personality-altering confidence-boosting drugs, if such were easily available and had no side effects.

So we have (1) a social solution, (2) a “not a real problem” solution, and (3) “wait for scientific and technological progress to fix broken biology/psychology” solution”.

gedymin 21 Jan 2015 10:41 UTC
5 points
in reply to: JoshuaZ’s comment on: The Unique Games Conjecture and FAI: A Troubling Obstacle

If UGC is true, then one should doubt recursive self-improvement will happen in general

This is interesting, can you expand on this? I feel there clearly are some arguments in complexity theory against AI as an existential risk, and that these arguments would deserve more attention.

To sidetrack a bit, as I’ve argued in a comment, if it turns out that many important problems are practically unsolvable in realistic timescales, any superintelligence would be unlikely to get strategic advantage. The support for this idea is much more concrete than the speculations in the OP of this thread; for example, there are many problems in economics that we don’t know how to solve efficiently despite investing a lot of effort.

gedymin 10 Jan 2015 11:11 UTC
0 points
on: Explaining “map and territory” and “fundamental attribution error” to a broad audience
Why do you think that the fundamental attribution error is a good point where to start someone’s introduction in rational thinking? There seems to be a clear case of the Valley of bad rationality here. Fundamental attribution is a powerful psychological tool. It allows us to take personal responsibility for our successes while blaming the environment for our failures. Now assume that this tool is taken away from a person, leaving all his/her other beliefs intact. How exactly would this improve his/her life?

I also don’t get why thinking that “the rude driver probably has his reasons too, so I should excuse him” is a psychologically good strategy, even assuming it is morally right.

About map vs. reality. Not sure why it has to be put together with FAE, as it’s a much more general topic. And your explanation is not the the first one I’ve seen about this topic that leaves a big “so what?” question hanging in the air. At the face value, it seems to say that “people often confuse the idea of an apple with an apple in their hand”. Now clerarly that is not the case for anyone, perhaps except the most die-hard Platonists. Even if it would be so, why should the aspiring rationalist care?

I think negative examples would be really strong here. Teaching about the perils of magical thinking and wishful thinking would be a good start. Only after giving a few compelling concrete examples it makes sense to generalize and speak at a more abstract level. It also seems that many aspiring rationalists / high IQ persons are especially vulnerable to the trap of building elaborate mental models of something, and then failing to empirically test them by experiencing the raw reality.

gedymin 7 Jan 2015 10:26 UTC
1 point
on: Exams and Overfitting
I don’t think that overfitting is a good metaphor for your problem. Overfitting involves building a model that is more complicated than an optimal model would be. What exactly is the model here, and why do you think that learning just a subset of the course’s material leads to building a more complicated model?

Instead, your example looks like a case of sampling bias. Think of the material of whole course as the whole distribution, and of the exam topics as a subset of that distribution. “Training” your brain with samples just from that subset is going to produce a learning outcome that is not likely to work well for the whole distribution.

Memorizing disconnected bits of knowledge without understanding the material—that would be a case of overfitting.

gedymin 5 Jan 2015 10:36 UTC
4 points
on: Compartmentalizing: Effective Altruism and Abortion

There is a semi-official EA position on immigration

Could you describe what this position is? (or give a link) Thanks!