Here are three basic truths that I have discovered:

1. Nobody has successfully discovered the secret to programming the VCR.

2. Gravity works, and it's not worth dying to test out alternative theories.

3. The Toronto Maple Leafs have no chance.

What does that have to do with explaining explanation and the
other arguments David makes about truth in his lecture, Peter?

Vit:
Perhaps I could explain what Peter means in terms that are understandable and prompts me to agree with what he (Peter) is saying.

(a) What Peter says is interesting.

(b) What David says is not.

On the other hand, maybe that's just me and my meaningless existence.

Yes, but that's hardly the point, BCer, is it? The point is that we have a symposium provided here for people who are interested in David's lecture, not for people who are not interested. If you are not interested in this symposium, then kindly piss off and go crap on someone else's parade.

....as with the 'undiscovered country'(bill wagstaff) reference t'other day this lecture's title reminded me of an apposite couplet of Byron's.

"while Bishop Berkeley explains metaphysics
to the nation
I wish he'd explain his explanation".

Beyond the title itself, John, what did the
content of David's lecture remind you of?

Reminds me of someone searching for the meaning of his own existence. Was thinking any moment there would be a consciousness raising session.

Meanwhile working people actually make the modern world he speaks so highly of go around.

1, In the box, shouldn't "vary" be "verify"?

2. Peter--What is a VCR?

Vit....

and i mean this seriously...

it reminded me of bob dylan's lyrics in his great scat tune 'if dog's run free" ?

which is i reckon just another way of trying to closer approach the Godhead.....as all scientists do...and all balladeers..

"That the truth consists of hard to vary assertions about reality is the most important fact about the physical world."

Seems axiomatic. Covers all the bases. Would seem to me to apply beyond the boundaries of the physical world as well, although Dr. Deustch explicitly excludes such considerations for the purposes of his talk.

Jeez, I must be in the wrong place. I don't understand a friggin' thing he, and others are talking about.
And then, if for some reason I point that out, I may be told to piss off and go rain on someone else's parade.
Nice, really nice.

No, Doug, it's vary, not verify, watch the lecture.

And I don't see, Hoss, how one can convert David's
study of the metaphysics of truth into a search for
one's existential axiology.

I agree with Exetaz. I think that David's point seems axiomatic, or at least almost so, upon reflection. Covers all the bases, as she says. At least in 20/20 hindsight. But have you ever heard it so argued before? And if not, is David's metric of truth not then a tool which upon appreciation we can effectively deploy? I can certainly entertain questioning my truth-beliefs based on their ease of variability. But then, I'm interested in what truth is, not in convincing others that I know what it is even if I don't.

It's a subtle point, but I figure it has to be worth careful consideration. Deutsch is a noted thinker, and he's gone to the trouble of explaining this for a specific reason. One ought not casually dismiss it with an "and you mention this because...?"

If all I get out of his talk is the idea that I should always looks for alternative (varied) explanations as part of the process of validating the truthfulness of the explanation I've arrived at, I'm ahead, yes?

I guess he's saying the physical world==reality and 99%of the time it's probably correct.
Intuitive&pastTheories can't account for everything.

Nay, nay, Atric, if you pointed out that you don't understand, I would attempt to assist you in further understanding, to the degree of my ability and of your interest. However, if you claim, as some do, that you are not interested in this symposium, then you don't belong here. There are others just down the hall, here's one of my favourite programmes.

I do indeed think, Exetaz, that there's something worth careful consideration in David's lecture this afternoon. I'm not saying I can explain it properly, or at least not yet, since I've only recently heard the lecture for the first few times myself, but there's something that makes the old metaphysicst in me sit up and ask: what did you just say, again? I don't think it's just about the truthfulness of an explanation, Exetaz, I think it's about the ontological nature of truth itself.

"it's about the ontological nature of truth itself."

Okay, say that another way. "Ontological" is a water-muddier of the first order when it comes to teasing the intended meaning out of subtle points - and I also do want to understand exactly what Deutsch is getting at.

It coverts thusly. The truth will make you free. He's so bound up in the imperfectness of his own mind he can't see the perfect. In other words, he can't see the truth. Without the beginning you can't know the end.

As I understand it, Exetaz, it's not so much about whether or not there are various explanations, it's about whether or not an explanation holds even if you vary the argument in structurally incompatible ways. If you can do that and the argument still holds then it's not a good argument. On the other hand, if the argument cannot stand if you vary the parameters in such a fashion, then that lends credibility to the degree to which the argument is true in that context.

Here's what I think is going on, Exetaz. The bottom three layers of philosophy are metaphysics (which includes ontology and theology), upon which sits epistemology (reason, logic, mathematics, sciance, &c) and upon which sites axiology (aesthetics and ethics, which is where humans first enter the picture). Now, by my classic understanding, we usually entertain the notion of truth at the axiological level in the vernacular sense, or possibly at the epistemological level in the more formal sense. But what of the very nature of the existence of truth itself, which would be its ontological metaphysics layer. That's what I think David's lecture is at least skating around; that's what I find fascinating. Not "Is X true?", but "What is truth?"

So the underlying question is how can we know what is true?

I think, Exetaz, that David is suggesting that it may be the case that one of the ways and perhaps the way we can epistemologically know how an explanation is or is not true is if we can determine whether or not the explanation passes the ontological test of not being able to be varied and then still be valid. At this level, perhaps the how is a function of the is: to know what is true is to know what truth is; to know what truth is is to know what is true.

But if one can vary the parameters of one's argument in the fashion illustrated by David in his lecture, and still have one's argument apply, then one has a bad explanation, as David defines it in his lecture.

Philosophers figured this sort of thing out thousands of years ago.

But, since too many people think that philosophy is a useless discipline, too many people haven't been exposed to the usual thinking on this issue.

Asking "What is Truth?" will give you no answer. You'll notice that everything is given to us from thoughts and perceptions, but even measurable things -- gravity, math, require our senses to verify.

BUT there is no way to verify that your senses are giving you correct information. You can sit in total paralysis where you can't verify a thing, which keeps you from doing literally everything -- if I can't verify 100% that I won't fall through my floor, then I shouldn't get out of bed! ... except, nobody truly believes this. Even Hume said he went back to living in reality like everyone else when he wandered away from his studying for a few weeks.

You have to use other words to describe what truth is -- just like anything. Ever had a kid ask "Why? Why? Why?", and when you become annoyed and say "Because it just IS!", that this is not good enough for the kid? They're on to something. For example, the dictionary uses words in the dictionary to explain words in the dictionary.

It's like the old joke about what keeps the world from falling down. Well, the world is sitting on a turtle's back. What's that turtle on? ...another turtle! What's THAT turtle on? ...don't you get it? It's turtles, all the way down!

Long story short? Take philosophy degrees. Then, once you know how to test for truth, take a different degree that you think someone like Capt Capitalism feels is worthy.

Name three thousands-of-years old philosophers who had this all figured out. Indeed, the entire set-up in David's lecture today falsifies that old shibboleth. If you had bothered to watch the lecture, Mm, you would not have thrown out that old sensory canard so flippantly, because David explictly addresses that in the lecture, ergo as a thinking man you would have responded to his conjectures. But you didn't. So you didn't. Meanwhile, the rest of us are moving forward on a concept you are unwilling to consider, which is your loss, sir. Unless, of course, like some other commenters who are not interested in today's symposium, you are just another troll. Because that's what one is who craps on a conversation they are not interested in: just another troll.

This is tough slogging for many of us, and I'm probably going to catch hell for commenting, but here goes: I think Vitruvius suffers from (or is gifted with) an obstinate persistence of intellectual curiosity. And this is good! However this David, like so many before him since the "enlightenment" again tries to tell us that Darwin's finches have more to tell us than (here it comes) priests. I guess he's not talking about those clergy who made huge scientific discoveries, however. And shouldn't priests be teaching ontological and theological matters as opposed to science? I'm not sure this is pertinent, but Chesterton says that "Reason is itself a matter of faith; it is an act of faith to assert that our thoughts have any relation to reality at all."

Keep in mind, Larben, that more than a few hundred years ago people like David and I would have been monks studying the nature of truth, in those days paid for by the church. Of course reason too is a matter of faith, but the ontology of truth goes beyond reason. As Pope Benedict XVI noted in his Regensberg Lecture: "Modern scientific reason quite simply has to accept the rational structure of matter and the correspondence between our spirit and the prevailing rational structures of nature as a given, on which its methodology has to be based. Yet the question why this has to be so is a real question, and one which has to be remanded by the natural sciences to other modes and planes of thought: to philosophy and theology."

So there you have it: today's lecture by David Deutsch is a contribution to the question of why, one which as the Pope mentioned has to be remanded by the natural sciences to other modes and planes of thought: to philosophy and theology. That doesn't mean it's necessarily not interesting to everyone. Frankly, some would probably go so far as to point out that David's foray is a classic example of the beautiful behaviour of human beings so eloquently described by Alexander Pope in his Essay On Man:

Know then thyself, presume not God to scan;
The proper study of mankind is Man.
Placed on this isthmus of a middle state,
A being darkly wise, and rudely great:
With too much knowledge for the skeptic side
With too much weakness for the Stoic's pride,
He hangs between; in doubt to act, or rest.
In doubt to deem himself a god, or beast;
In doubt his mind or body to prefer,
Born but to die, and reasoning but to err;
Alike in ignorance, his reason such,
Whether he thinks too little, or too much:
Chaos of thought and passion, all confused;
Still by himself abused, or disabused;
Created half to rise, and half to fall;
Great lord of all things, yet a prey to all;
Sole judge of truth, in endless error hurled:
The glory, jest, and riddle of the world!

Vitruvius, you're certainly making it easier to be "not interested in today's symposium".

What do you think about what David said, Ural?

I always wondered why he was remembered for the Rape of the Lock. It doesn't really answer any questions, but it's not supposed to I suppose, but it does show why faith is so important to mankind and can never be totally extinguished.

An interesting lecture to be sure... twice for me, but without a complete and true understanding. I found Pope Benedict's Regensburg Lecture (reading it) much easier to wade through, to hold as something attainable in mind. That perhaps, "I got it". Dr. Deutsch forwards his ideas in a manner that grates me, and perhaps I should have read one of his lectures, instead of listen to him. A minor point maybe, but I'd fail a class given by him for the same simple reason. He does tie things up at the end nicely, I appreciate that by most people in the sciences. Thanks for the link Vitruvius.

Faith, by which we mean belief, is so important to mankind and will never be even partially extinguished because belief is what our brains do for a living, Larben. David talks about this in today's lecture. It's the way our brains work. Not working that way is called crazy.

Yet if you think about it there's not much there there. What is true is true even if we don't exist (other than details about us, of course). So the nature of truth transcends axiology, and I think David is arguing in his lecture, and I think I agree with him, that the nature of truth even transcends epistemology, and reaches to the metaphysical, via the structure David describes.

And I think we all appreciate your point about the limitations of David's style, Marc, though I do have to wonder when faced with all the tap-dancing shysters (no offence to tap-dancers intended, of course) whether or not the aspergian quirks of a simple genius like David aren't the least of our problems.

Vit,

Ordinarily I would have watched the video before commenting - I didn't this time. I have an ear infection ... and watching the world series ... can't watch the video and do the WS at the same time. I'll do the vid after the WS.

I have varied opinions about the TED talks - the whole range ... from nutbar to right on. I suspect most people do. I find calling someone a troll, or shutting down a conversion, because of your agreement with any premise, unacceptable (to me).

I really want the ET's of the world to say a stick can find water ... because of whatever.

Having said that, I haven't found any of the TED talks that haven't got me to agree/think about something.

I want (juvenile, I know) you to either open these up or stop doing them. Your opinion is valued - why berate/censor?

As my favourite philosopher/scientist said, "There are Real things, whose characters are entirely independent of our opinions about them; those Reals affect our senses according to regular laws, and, though our sensations are as different as are our relations to the objects, yet, by taking advantage of the laws of perception, we can ascertain by reasoning how things really and truly are; and any man, if he have sufficient experience and he reason enough about it, will be led to the one True conclusion. The new conception here involved is that of Reality". (Peirce 5.384).

Whew. Essentially, he's saying that reality exists 'as itself' outside of our phenomenological perceptions. It's there, objectively, and is quite indifferent to our attempts to deny it, or linguistically mould it (eg, IPCC).. or vary it. And, unlike the postmodernists and socialists who have retreated to their subjective nominalism, reality exists, ontologically, despite us and our words about it.

Peirce was an Aristotelian...great stuff.

His explanation invokes hypothesis as a descriptive narrative with a minimalist plotline. I find this deficient. It differs only in degree with the approach taken by all cultures throughout history. As an heuristic approach, it has some value. If the initial “storyline” is broadly “correct”, then progress by accreting more detailed subplots (i.e., parameters) is possible. If not, then one gets epicycles.

No, I think the more fundamental explanation for the surge of material progress was a cultural realization (dominated by pre-enlightenment Europe) that the “story” was meaningful and sensible.

Yes, I agree, ET, yet the question remains: how do we judge that metaphysics. We can't do it "outside ourselves"; we don't live there. But seriously, don't you think that the notion of an invariance constraint upon hypothesis is a reasonable limitation to the applicability of reason? I mean, we can't just have variant hypothesis running around willy nilly, the Bursar won't have it ;-)

And what, exactly, does the surge of our material progress have to do with the ontology of truth, Tenebris? I'm not convinced, by your argument, that David's structure isn't more potent than you accredit to it. If one has a basket of truth-conjectures, and there are some that are trivial to take out without upsetting the basket, because they are variant in the fashion David describes, then I don't think they are as valuable as those conjectures the withdrawal of which would cause a large set of observed phenomenon to flounder sans explanation.

Thus the whole new way to explain explanation shtick.

Et lux in Tenebris lucet (I think)

"he's saying that reality exists 'as itself' outside of our phenomenological perceptions."

Well that's the conclusion some basket case, old Semitic nomad realized as he stared at a fire and heard these words, "I AM that I AM".

I believe that predates Aristotle by a few centuries.

Here's Marcus du Sautoy discussing symmetry, http://www.youtube.com/watch?v=415VX3QX4cU&feature=channel, a subject that I find illustrates the essential understandability of nature.

I wonder at what point Kate asks you circle-jerkers to take it off line.

I agree that Marcus du Sautoy's lecture is excellent, Tenebris, it's currently on my list for a future DLDI show, though that may be obviated now ;-) You may also wish to check out Lawrence Krauss's 2009 AAI Lecture, Tenebris, it's another interesting piece of the puzzle, I think. I'd pay good money to see Deutsch and Krauss go over the multiverse conjecture hammer and tongs!

‭I wonder when Kate will ask you circle-jerkers to take this off line.

This was censored by Vit ... he deleted try 1 - this is try 2.

Yes, there IS a restraint and restriction on hypotheses, set up within the boundaries of reason, of Ockham, and of objective perception of the pragmatic operation of those hypotheses.

However, our hypotheses must be open to such actions of reason and such empirical testing. I'll give as an example, the Darwinian hypothesis, or rather, the neoDarwinian hypothesis which has moved itself outside of testing. Its premises of random mutation and natural selection are, if I may say, not standing up to the hypotheses and tests of others in the science realm who think that evolution and adaptation are more interesting and complex than the neodarwinist hypothesis. My point is only that truth exists but, as you note, we don't live in that realm and do have to keep an open mind.

Tenebris, I disagree with your view that Western material progress was based on a cultural acceptance of various physical and chemical realities. Ideas usually develop AFTER material realities.

I think that the material progress of the West was a demographic necessity. Due to the extremely rich biome of Western Europe, the population kept rising beyond the carrying capacity of the current agricultural economy..a local peasant sustenance production, operated within a rigid two-class feudal system.

The rise in population led to poor nutrition, disease, famine..which decimated the population..which then rose again. The West tried to expand its resources (wars) which helped only marginally. Finally, and as the last tactic, the West had to change its economy. It had to develop the technology to produce more food, and market this to a wider area.

This required a social and political change, to enable a free-thinking, entrepreneurial and innovative class, the rise of the middle class..which began to interact with the envt as individuals, to question, to dissent and so, to develop new technology and so on. The old scholastic realm with its certainties of hypotheses collapsed..and the West's power emerged. All because, of course, of that rich biome of Europe....

I have, Ural, been doing this DLDI symposium shtick for ca. six months now, and Kate has not complained about it. It is a rare, once every few weeks, one in a hundred SDA entries event, that does not operate by the normal rules of the other entries here, it operates by my rules for these symposia. I have made this clear on multiple occasions in the past, on occasion addressed directly to you. Under the circumstances, it seems to me that people who complain about this phenomenon are like people who know that they get gas when they eat something in particular, and then they insist on eating it anyway, and then they complain about getting gas. Take it to someone who cares, I say.

"Name three thousands-of-years old philosophers who had this all figured out. Indeed, the entire set-up in David's lecture today falsifies that old shibboleth."

You already say that David has already singlehandedly dismissed every ancient philosopher. So, even if I name ancient philosophers, you have already dismissed them! Why on earth should I name them? David is already correct. You may as well ask me to explain phrenology -- then say, but since it's been disproved I won't even listen to you.

"If you had bothered to watch the lecture, Mm, you would not have thrown out that old sensory canard so flippantly, because David explictly addresses that in the lecture, ergo as a thinking man you would have responded to his conjectures. "

You're conluding that I would have not discussed sensory input (assuming that I had not watched the video). You say that I would not have discussed sensory input because David addresses this. Therefore, if I had watched the lecture, I am not a thinking man (that I am a thinking man is now officially a function of responding to his conjectures). If you could prove that being a thinking man is dependent on watching him, I would agree. But you didn't, so I won't.

Thinking woman, really.

"Meanwhile, the rest of us are moving forward on a concept you are unwilling to consider, which is your loss, sir."

ASSUMING that David is right! You're very willing to live your life according to the man (who has nothing to say in the least of ethics and politics, which makes it impossible to live by his words since they contain no instruction), and you are unwilling to have some kid stuck in her residence with the h1 disagree with this chump who makes vast claims about how prehistoric people must have thought about absolutely everything. How do we know what they were thinking if they were prehistoric? He's just making things up to make his lecture sound profound. You're allowed to question how he knows these things. He is making sweeping claims about the pre-Scientific revolution world. He's making claims about what all empiricists think! And you'd swear that he's figured out the entire philosophy of mind. Look up Dennett on Ted Talks if you want to, he is a philosopher of mind and studies consciousness. I don't really buy his theories though -- I believe in those trash 3000 year old philosophers too much to accept his methods :).

"Unless, of course, like some other commenters who are not interested in today's symposium, you are just another troll."

...therefore, being a troll (since you have proved this to yourself), you won't hear a word out of my mouth. I'll keep in mind that carping on other conversations I'm not interested in makes me a troll. Especially next time people are yapping in the library and I get mad at them -- I'm a troll! And especially when I disagree with a blogger and make a post -- after watching a TED video -- explaining a few things on an epistemological plane about sense perception.

As a fun side note: metaphysics is just the name of a book by Aristotle that comes after (meta) his book on the physics. It just happened to be about knowing knowledge.

Circle jerk is right. What can anyone say, practically, that they can do today they couldn't do yesterday?

Vit,

Thank you for your explanation (and for un-deleting my 1st post).

You have changed my mind - good job, your awesome. All you circle-jerkers are awesome.

I appreciate these symposia. The discussion extends my understanding on variety of subjects, and I always learn something. If it's a topic that doesn't interest me, I leave it aside, as Vitruvius recommends.

This is an oasis of erudite debate, not a circle jerk. It's good to see something other than current events and politics explored and debated here once in a while.

Excellent, Mm, well argued, you'll find some of Dennet's work in our previous symposia. Sorry, Hoss, I wish I could have helped. And you're welcome Exetaz, I try. To recap before nightcapping then, folks, the point is a new way to explain explanation: "That the truth consists of hard to vary assertions about reality is the most important fact about the physical world". And I've certainly enjoyed the repartee above, even though the topic is so hard for some to grasp; I sincerely hope you all have too, and so until at least tomorrow, good night everyone, best wishes, and thanks as always Kate for the opportunity to have this forum. Please don't forget to tip the barmaid on your way out.

Obviously nothing. Good night :)

exetaz: "It's good to see something other than current events and politics explored and debated here once in a while."

We are in complete agreement on this. The question is - why would someone be berated as a troll, as Mn was, in regards with something that is non-trollable? Am I missing something?

I think an explanation that monologue and dialogue inhabit distinct different realms might be apropos.

But, to the conversation…

ET – I find your Darwinian explanation for European progress singularly unconvincing. It is an explanation ex post-facto, easy to vary. Fecundity is not exactly rare, nor are constraints on easily accessible resources. Why did Europe take the road never traveled?

I know the thread's dead, but as an amateur student of medieval and ancient history I don't think ET's explanation of the rise of whatever in Europe matches the facts. It's pretty well accepted by most historians that a fluke cold winter caused the yersinia pestis outbreak in the 14th century, which killed off so much of the population that the peasants were no longer a disposable commodity. The fact that one individual's labour was suddenly worth so much more was the real cause of the rise of the middle class.

That and there were a lot more than two classes in medieval Europe. "Peasants" and "aristocracy" is a pretty aggressive oversimplification.

NO, Vit. I will not tip the "barmaid" on the way out.The site owner,yes. You? Not a chance.

I didn't say Mm is a troll, Ural, I said that arguments that thousands-of-year-old philosophers obviate David's thoughts and it's just turtles all the way down is not moving forward on the concept he is considering in today's lecture, unless one is a troll. You can't leave out that unless, Ural, without changing my intent from a conjecture to an assertion. Fortunately Mm went on to explain herself further, much of which I agree with. Yet it's not that sensory empiricism isn't without its uses, as David mentions as well as Mm, rather it's that we already know that we don't actually sense reality, we only sense the signals that reality transmits to us.

So we are still stuck with the question of what truth is. And yes, I appreciate that some people aren't interested in what truth is, they are only interested in what is true. That's fine, at least until we get to non-obvious questions of truth, such as some of those questions David raised about the nature of the fabric of reality in his lecture that we hosted in our 2009-01-25 symposium, or some of other questions people like Hawkins, Dennett, Gilbert, Strogaz, Ariely, Wolfram, Chaitin, et al have raised in some of our other symposia. But I still think the rest of us should be allowed to and should have a place to discuss questions like the nature of truth and whether or not the only thing that actually exists is information, without being fired upon by snipers who are not interested in discussing such questions in the first place. After all, this is a symposium, not Mm's library ;-)

And sorry I wasn't clear, Justhinkin, but I'm not a barmaid.
It was only an old joke that I apparently didn't tell correctly.

And yes, I appreciate that some people aren't interested in what truth is...

It's not that some people aren't interested, it's that some people recognize the futility of building another tower of babel.

Obviously Hawking and this nut don't believe their theories (many worlds)enough to kill themselves and test them. That would be truth.

Let us see now.

A new way to explain explanation

@3:10… mysteries and new unexpected phenomena…..all that discovered in forty years…had not been in previous hundred thousand….not for lack of thinking….they even arrived at answers (the early thinkers) such as myths…yet bore not resemblance to the truth. …..knowledge of physical world and how to adapt it to our wishes…what has changed?....universal truth that made it possible to know.
Before scientific revolution, they believed that everything important, knowable was already known enshrined in ancient writing…and some genuinely useful rules of thumb which were however entrenched as dogma.

Would it mean that a useful rule of thumb is to be thrown away because it is entrenched in dogma?

Listening, one may think, by stated arguments that the new way to explain explanation maybe just that.

Do the statement and the lecture assume that the new way is the corredt and final answer?

The assumptions about today’s knowledge may be brought down tomorrow or next year or….horizontal 8. As the arguments in the lecture rather airily bring down earlier assumptions of knowledge?

Just making an argument by non academic.

tenebris - analyses of history are always ex post facto. And it is most definitely not a Darwinian explanation. There's no randomness, no natural selection involved.

It is a biological and ecological AND rational explanation, understanding human societies as constrained by both factors, within a distinctly human rational ability to change the perimeters of those biological and ecological constraints..by the use of their reason.

Resources? Such as switching from local simple agricultural sustenance to mass surplus production for markets? Releasing peasant labour to urban production of goods? Europe took the road 'never travelled' because it was the only ecological area on this planet with such a biome: regular rainfall water souroce, extremely rich soil, animals that could be domesticated, temperate and regular climate.

Put that together, and you get a capacity for a large population. BUT, you still need the technology and the ideology to produce mass supplies rather than local village needs. This means an innovative population and a market oriented population. Europe moved into a middle class economy because it had to - its population grew beyond its economic and political constraints. It had to move out of dogma of 'we know it all' to discover new technologies and new ways of economic and societal life.

Daniel Ream - sorry, but I'm not an amateur student of these issues. There was not 'one' plague in the 14th c, but a series of outbreaks and you can go back into the 10th c for these, along with other diseases and famines. Then, you have to check out the various 'tribal' or fiefdom wars both internally and with foreign states. Then, you check out the resurgence of populations after each decimation by disease or war.

Also, check out the political infrastructure of power; it was two-class, the upper class and lower class - and the terms aristocracy and peasant are quite valid. Eventually, this infrastructure, which denies information gathering and knowledge and economic and political power to the lower class..had to change.

I'm sure you know of the rise of the 'dissenting individual' e.g, Abelard's famous statement of 'dubitando' (I doubt), an intellectual statement unheard of in The Faithful. This refocusing of knowledge within the individual rather than The Authority (the Church) was a long fight, but it enabled the rise of the middle class, who then took political and economic power.
This class then moved to aggressively change the economic mode of production, moving to a market rather than local sustenance economy,..to developing new technologies and the enable man to objectively observe and control his environment.

None of this was caused by one plague, which then so depleted the manpower that, eureka, the powers that be, suddenly recognized the value of human labour and so caused the middle class. Nonsense. Such an enlightenment did not occur. The whole change took over 400 years, filled with counter fights, repression, and a long, slow intellectual movement, and a long, slow economic transfomration from a rural and local economy to an urban market economy.

I don't think, Lev, that David was suggesting that "genuinely useful rules of thumb which were however entrenched as dogma" should be, as you put it, "thrown away", but rather that to the degree that we humans are able to advance our understanding of what truth is and what is true we are thus better able to move said useful rules of thumb from the field of engineering down into the fields of science or perhaps even philosophy, which would be a good thing. The more we can know about what actually is, rather than about what we suppose there to be that nevertheless isn't, the better we will be at avoiding the types of errors and mistakes that result from those cases which actually are caused by bad data wrongly elevated to the status of dogma.

Thank you Vitruvius for writing in plain language, see, it works just the same, perhaps even better for most plebeians (though to say “most”, I agree is despicable).
The “thrown away” was rather a figure of writing and less of meaning.
The trouble with intellectuals is that for them the word “truth” has limited application if not being meaningless what so ever.
The limited application would be, when talking down to those they deem of lesser ability to think, because it is intended to sound good as opposed to a statement of fact.
In a philosophy class the instructor and books would talk about “empirical truth” if I’m not mistaken that would be “self evident”, a syllogism of expression, perhaps subject to dispute on minor point, though not in error.
As you no doubt know from Descartes, nothing is, everything is based on person’s perceptions. Ultimately in the extreme the only “it is, because it thinks”.
Of course the whole treatise is an excellent philosophical exercise though it fails in real life.
Now as for self evidence of truth as opposed to perception I proposed that the instructor walks against the wall of the school room and see what happens if he insist on perceiving that wall is not. The instructor being of superior mind refused to discuss it, his attitude seem to harden somewhat.
Anyway it is good to have a chat.

Well, I'm going to side with ET and Peirce on this one, Lev, and not Descartes: I think that what is is independent of our perceptions of it, except in those cases which are our perceptions or are dependent on our perceptions. If some star in some galaxy billions of light-years away from us decides to go all super-nova, our perceptions don't enter into it.

But we're straying from David's topic again, namely that to the degree that we have explanations about things like stars and super-novae, then all other things being equal, those explanations that are harder to vary are better explanations. It's sort of like the addition of another instrument, one like Occam's razor, to mans' philosophical toolbox.

More importantly, perhaps, are questions of extreme truth that sometimes come to light when scientists and engineers like David and I work on edge-case nano- and mega-scale technologies in order to help further bring the good things in life to all you folks.

I do think that it is good, as you suggest Lev, to have a chat. Since my lowly degrees are in science and engineering, it is with curiosity and fascination that I approach these rather grander questions. To me, the very concept of explaining explanation is the perfect excuse for a symposium and a few kraters, about which you may recall Euboulos's note to the effect that:

For sensible men I prepare only three kraters: one for health (which they drink first), the second for love and pleasure, and the third for sleep. After the third one is drained, wise men go home. The fourth krater is not mine any more - it belongs to bad behaviour; the fifth is for shouting; the sixth is for rudeness and insults; the seventh is for fights; the eighth is for breaking the furniture; the ninth is for depression; the tenth is for madness and unconsciousness.

What continues to puzzle me though are the cases of those who mistake my joyful glee for some sort of intellectual, academic snobbery. One of my friends has suggested that some people simply can't believe that I am as guileless as I actually am, so they naturally attribute intentions to me that I don't actually have. Another of my friends has suggested that it's simply a characteristic of the medium: that some people only come to the blogs to be assholes, and nothing one says really matters to them either way, as long as they can just continue to spew. Of course, this latter chap's degrees are in psychology, so what does he know about human behaviour ;-)

This being the hour of the termination of our scheduled interregnum for this week's symposium, I'd like to take this opportunity to thank once again all those who have enjoyed participating in this week's show. I look forward to seeing you all again during our next symposium, and as I mentioned supra, thanks for this space-time, Kate.

This symposium is now closed.