Consider the hypothesis: On August 1st 2008 at midnight Greenwich time, a one-foot sphere of chocolate cake spontaneously formed in the center of the Sun; and then, in the natural course of events, this Boltzmann Cake almost instantly dissolved. I would say that this hypothesis is meaningful and almost certainly false. Not that it is "meaningless". Even though I cannot think of any possible experimental test that would discriminate between its being true, and its being false. I would say that this hypothesis is meaningful and almost certainly false. Not that it is "meaningless". Even though I cannot think of any possible experimental test that would discriminate between its being true, and its being false.

Well, if you had access to a time machine and some sensing device that could survive the environment of the Sun...

Yeah, I'm a nitpicker. I'm also not as good at picking nits as I might like.

I've an old post - 'Verification and Base Facts' - which shows how a non-verificationist can still capture much of what was most compelling in verificationism.

An idea unconfirmable by experiment is not just probably wrong, but necessarily meaningless.

If it's unverifiable-in-principle, there is no distinction between the affirmation and negation of the premise, and the concept is meaningless.

The positivist accusation seems obviously false just based on the whole quantum mechanics series of posts.

On second thought, that's not right. But you probably understood what I mean. If you happen to make an a conjecture about something like Kolmogorov complexity or the halting problem, and it just happens to be undecidable, it's still either true or false.

The Kolmogorov complexity of this sentence is exactly 50 bytes in Java bytecode. Meaningful, but unfalsifiable.

You can't make a Java class file that small.

Maybe you mean the difference between the smallest possible executable class file, and one that prints that message will be exactly 50 bytes, given some specified existing standard library? If so, the sentence should probably make that clearer.

I haven't gotten through your whole post yet, but the "postmodernist literature professor" jogged my memory about a trend I've noticed in your post. Postmodernists, and perhaps in particular postmodernist literature professors seem to be a recurring foil. What's going on there? Is a way to break out of that analytically? I sense that as a deeper writer and thinker you'll go beyond cartoonish representations of foils, if nothing more to reflect a deeper understanding of things like postmodernist literature professors as natural phenomena. It seems to me to be more a barrier to knowledge and understanding than an accurate summation of something in our reality (postmodernist literature professors).

No, I still think there's a difference, although the omnipotence suggestion might have been an overly hasty way of explaining it. One side has moving parts, the other is just a big lump of magic.

When a statement is meaningful, we can think of an experiment that confirms it such that the experiment is also built out of meaningful statements. For example, my experiment to confirm the cake-in-the-sun is for a person on August 1 to go to the center of the sun, and see if it tastes delicious. So, IF Y is in the center of the sun, AND IF Y is there on August 1, AND IF Y perceives a sensation of deliciousness, THEN the cake-in-the-sun theory is true.

Most reasonable people will agree that "Today is August 1st" is meaningful, "This is the center of the sun" is meaningful, and "That's delicious!" is meaningful, so from those values we can calculate a meaningful value for "There's a cake in the center of the sun August 1st". If someone didn't believe that "Today is August 1st" is meaningful, we could verify it by saying "IF the calendar says 'August 1', THEN it is August 1st" in which we specify a way of testing that. If someone doesn't even agree that "The calendar says 'August 1'" is meaningful, we reduce it to "IF your sensory experience includes an image of a calendar with the page set to August 1st, THEN the calendar says 'August 1'." In this way, the cake-in-the-sun theory gets reduced to direct sensory experience.

To determine the truth value of the uncle statement, I need to see if the Absolute has an uncle. Mmmkay. So. I'll just go and....hmmmm.

If you admit that direct sensory experience is meaningful, and that statements composed of operations on meaningful statements are also meaningful, then the cake-in-the-sun theory is meaningful and the uncle theory isn't.

(I do believe that questions about the existence of an afterlife are meaningful. If I wake up an hour after dying and find myself in a lake of fire surrounded by red-skinned guys with pointy pitchforks, that's going to concentrate my probability mass on the afterlife question pretty densely to one side.)

It's not clear that you're a verificationist but you're clearly an Empiricist. I think that's problematic. Unless you believe something magical happens at the retina, then there's no more reason to privilege what happens at the retina or in the brain, than there is the wire connecting the dial to the voltmeter. It's all causal linkage. We can use the same standards of reliability for people as we do wires. The sensory periphery is just not particularly interesting.

"There exists a invisible dragon in my garage, which can't be seen, felt, or sensed by any methods known to man today, or in the future".

This is meaningful and true according to MWI.

Poke, can you expand a little on what you're driving at?

Also, Steven, how on Earth is that statement true under MWI? :)

The dragon is in another world superimposed on ours, one where something improbable happened (some form of genetic engineering?); we will never be able to interact with the dragon in any way, but it's perfectly real, as the people (also invisible to us) in its world can verify.

That dragon isn't in our world, steven. It's not in the garage. The people to which the dragon does exist aren't in our world or our garage, either.

The original claim is meaningless.

Honestly, I think that academic disciplines, or even schools, where everyone is completely full of it are extremely rare.

Most of those ideas were worthless. Most modern ideas are worthless, too. The question is: how good were they at distinguishing the worthy ideas from the worthless ones? The sheer number of recently-discarded fields, much less ideas, should make it clear how well the ancients discerned the gold from the dross.

What's the signal-to-noise ratio? How much care is taken to ensure that people aren't deluding themselves?

michael vassar, Maybe that's a good description of new departments (eg x-studies), but you sound like you think the post-colonial rhetoric is coming out of political science departments rather than English departments.

...and I go on to learn that people in political science departments cite Derida.

Political science is the department where it would be most interesting to know what's going on because it has methodological pluralism while seeming to have a single topic, while, say, English departments seem to have gotten methodological variety out of crisis of topic.

This seems like an excellent example of the application of the Law of the Minimum - admittedly, outside of the specific ecological context it was formulated in, but the general principle is sound.

The resource in least supply will dictate the growth of the population, and the entity that requires the least expended or committed resources while meeting the minimum standards will dominate the population.

Fields that have low standards will be dominated by garbage. Fields with high standards will be dominated by whatever can pass those standards.

What are the standards that determine whether work in a field is valuable? Not from the viewpoint of those within the field, but from a general perspective? Once that's determined, we need only see which fields' requirements best match those standards.

I just finished reading Ayer's "Language, Truth & Logic" last night, and from my understanding of it, I think he'd think that your proposal about the appearance and vanishing of a chocolate cake was a meaningful proposal. He said, for instance, that it would be meaningful and reasonable to posit the appearance of wildflowers on a mountain peak nobody had climbed based on the fact that such wildflowers had been seen on similar mountain peaks nearby, or to propose that there were mountains on the dark side of the moon (before it was possible to empirically verify this). He seemed mostly interested in disqualifying propositions that were /in principle/ unverifiable. Now if you're asserting that this piece of cake came and went /and/ that it's not just going to be really difficult to come up with a single sense-impression that this fact would have some bearing on, but that it is /in principle/ impossible to do so, then he'd probably say you're talking rot.

Your example of a spaceship exiting the range at which you could possibly have any interaction with it is another issue. Ayer deals with the "does this tree continue to be when there's no one about on the quad" question, and says that (if I remember right) since the logical construction "this tree" is composed of both actual and hypothetical sense experiences, there's no reason why you have to imagine it vanishing when those sense experiences aren't immediately occurring. Even given this, though, I'm not sure if Ayer would call your spaceship meaningless or merely improbable, since its hypotheticals would all seem to be logical impossibilities.

If statements which are not testable are meaningless, then the statement "Statements which are not testable are meaningless" is meaningless.

Can you show it to be untestable? Or is there a way you might check?

If all you are worried about is in-principle verification, then, so the argument goes, the way to check is to see if there is any empirical content to "statements which are not testable are meaningless." What is there in the world that we would see if that statement is true?

There are three categories -- "meaningful," "meaningless," and "tautological" statements -- at least in Ayer's categorization. "Statements which are not testable are meaningless or tautological" would be an example of a tautology: just a definition of terms.

Because if you /could/ test the statement to see if it were true (not absolutely true, but, per Ayer, "probable"), you'd conduct an experiment where you took a sample of statements, tried to come up with tests (ways in which they refer to sense experiences that would serve to verify or disprove them), and then saw which ones were or were not meaningful. But in Ayer's framework, meaningfulness is defined as referring to sense experiences that would serve to verify or disprove, so it's circular, thus tautological, which isn't a term of abuse in Ayer's categorization the way meaninglessness is. He thinks that philosophers deal in tautologies all the time -- constructively! -- and that meaningful statements are more in the domain of science anyway.

he way to check is to see if there is any empirical content

Is there something which I can do as someone accepting meaningful untestable beliefs that I can't do as a positivist? Certainly there is some meaning to the sentence:

On August 1st 2008 at midnight Greenwich time, a one-foot sphere of chocolate cake spontaneously formed in the center of the Sun; and then, in the natural course of events, this Boltzmann Cake almost instantly dissolved.

but the positivist might simply say that you can give this a meaning, but science does not need to to do its job. I'm not saying that there isn't an advantage to talking about the meanings of sentences without experimental results, i'm just saying that to refute positivism you have to show that science does something you cant do by simply defining beliefs in terms of predictions. You have to give an example of science doing something successfully which commits it to the meaning of an untestable belief.

Interesting post, which I would like to make some comments to.

First of all, I don't think it's necessarily a bad thing to be associated with the logical positivists. In their days, they were, in my view, one of the most interesting proponents of the scientific world-view. The fact that their program (which was unusually well specified, for being a philosophical program - somethinghat contributed to its demise, since it made it easier to falsify) ultimately was shown to be unviable does not show that their general outlook was mistaken. Verificationism and the notion that philosophy should construct a scientific world-view can still be good ideas (in fact are good ideas, in my view) even though the logical positivists' more specific ideas were misguided.

Secondly, Yudowsky is right that unverifiable statements are not meaningless in the same sense as true nonsense is meaningless. In his essay "Positivism Against Hegelianism", Ernest Gellner makes the same point:

"The logical positivist definition of meaning was inevitably somewhat confused. Clearly, though, it could not define 'meaning' in the sense used by working linguists as he classes of sound patterns which are emitted, recognised and socially accepted in a given speech community. By such a criterion, 'metaphysical' [i,e. unverifiable - my note] statements patently would be meaningful. The anti-Platonism of paradigmatic logical positivism equally prevents us from interpreting the delimitation of meaning as the characterisation of a given essence of 'meaning', as for them there are no such essences (thiugh in some semi-conscious manner, and in disharmony with their nominal anti-Platonism, I strongly suspect that this was precisely what many of them did mean).

The only thing which in effect they could mean, plausibly and in harmony with their other principles, was this: the definition circumscribed, not the de facto custom of any one or every linguistic community, but the limits of the kind of use of speech which deserves respect and commendation. It was a definition not of meaningful speech, but of commendable, good speech. Their verificationism was a covert piece of ethics. Meaningless was a condemnation, and meaning a commendation." (Gellner, Relativism and the Social Sciences, pp. 30-31)

As I argue in my article "Ernest Gellner's Use of the Social Sciences in Philosophy" (Phil of Soc Sci, 2014:1), this interpretation is not quite right, though. Gellner's interpretation is over-charitable - the logical positivists really did saw their assertion that unverifiable statements are meaningless as descriptive (even though Gellner is right that they at some level intended it to be normative). More importantly, so did their chief critic Quine who dealt an important blow to logical positivism by showing that that the logical positivists' conception of meaning failed to illuminate how language actually works (in "Two Dogmas of Empiricism"). He subsequently argued that it should be replaced by his own notion of stimulus meaning - a behaviouristic notion which he held to be empirically acceptable, unlike the logical positivists' notion of meaning. (Word and Object)

The logical positivist notion of meaning was, in short, not empirically grounded in any way. They just asserted that some statements are meaningless, and some are not, while producing little argument for it - and certainly no empirical evidence. My guess is that there is an important lesson to be learnt here. For all their talk of a scientific world-view, the logical positivists were rather influenced by the German tradition of a priori philosophy (e.g. Carnap was influenced by neo-Kantianism). Also, there was a strong anti-psychologistic trend in early 20th century philosophy, inherited from the 19th century (especially Frege: for an excellent overview over why psychology was severed from philosophy in Germany, read Martin Kusch's Psychologism: A Case-Study in the Sociology of Philosophical Knowledge, where it is convincingly argued that this happened for social, non-rational reasons.

Naturalistic philosophers have for centuries tried to make philosophy more empirical and more based on the sciences, but although some progress is done, it seems that it seldom goes far enough. E.g. the later Wittgenstein – in many ways a naturalistic philosopher - argued that philosophers should "not think, but look", and that we should look upon language in an "anthropological way", seeing how it really works (rather than constructing a priori models, as philosophers often had done). Still he did no empirical investigations himself. Likewise the logical positivists venerated science but used a non-empirical notion of meaning.

There might be several reasons for this, but the most important one seems to me be that philosophers are more or less exclusively trained at a priori-reasoning and don't really have a lot of other useful knowledge - certainly not cutting-edge knowledge. In order to make philosophy thoroughly naturalistic, philosophers must - as has been argued on this site - be extensively trained especially in cognitive psychology (which I hold to be the empirical discipline most useful to philosophers) but also as far as possible (and depending on specialization) in other disciplines.

Lastly I would like to add that Karl Popper’s famous falsificationism was probably closer to Yudowsky’s thinking, since Popper did not see falsifiability as a criterion of meaning, but rather as a criterion of whether a theory should be seen as scientific. Popper was, though, much more positive to metaphysics (e.g. he was a realist) than the logical positivists, and I’m not sure if Yudowsky would like to follow him on that point.

I'm not sure your interpretation of logical positivism is what the positivists actually say. They don't argue against having a mental model that is metaphysical, they point out that this mental model is simply a "gauge", and that anything physical is invariant under changes of this gauge.