This is one of the rare lectures which had a profound influence on my way of thinking. David Deutsch has an amazing capacity of spotting and presenting complex philosophical and scientific ideas. He's a true genius!
His brilliance and explanation also led me to regard epistemology and knowledge as the paramount philosophy. Also, unexpectedly, helped me resolve several personal professional struggles.
@@george5120 But it does have to do with the beginning of infinity. Except hes not talking about the infinity of time, he talking about the infinite growth in scientific knowledge.
@Dr Wannabestein He's trying to condense the ideas in his book into a short speech and he doesn't do it brilliantly. The book is an excellent but slow burner. His ideas are astonishing
Fully agree. This is TED classic. The only one we should have. For the last 10 years I can't stand TED. I love listening to experts and insightful people.
"That the truth consists of hard to vary assertions about reality is the most important fact about the physical world. It is a fact that is, itself, unseen yet impossible to vary."
His delivery is off the cuff, the notes are there to let him know in what part exactly of his speech he is in. Memorizing a delivery is a way to automatize your delivery, to narrow the way you think about it so that you can't deviate from how you memorize it. Instead he understands what he has to say and the notes do the job of keeping a fixed structure in the speech
Deutsch is easily the most consequential and insightful thinkers I have heard in decades. I listen to people with incredibly half-baked grand theories, like Yuval Harari for example, and I am saved from being taken in by applying the ideas of Deutsch.
@@EmperorsNewWardrobeharari’s theories (in my view) are somewhat regressive, seeming to imply a lot of our development has been to our personal detriment, and humanity was better off when we were merely foragers. Deutsch by comparison says the opposite: that our survival depends on relentless innovation and growth and the pursuit of knowledge. I might be misreading Harari but I think this encapsulates the main difference in their respective messages
Please understand something: This man is one of the most brilliant thinkers of the modern era, despite being far less well known. In his various works, he presents a wholistic way of understanding the universe as it is currently known, from a basic level of core principles and patterns that can be seen in all aspects of human existence. I highly reccoment The Fabric of Reality and the Beginning of Infinity. They can be a bit hard to comprehend but if you take the time to read them they will genuinely make you a smarter human being.
00:00 00:18 Wondering in terms of things unseen. 01:57 The world never improved, nothing new was learned. 03:49 What had changed that made the difference between stagnation and rapid open-ended discovery? 06:21 Empiricism: Knowledge comes from the senses, not mathematics 08:21 No one’s ever seen evolution, we see rocks. 09:37 Testable conjectures are common in myths. 11:17 What is a bad explanation? 12:55 What makes the difference between good explanations and bad explanations.
16:13 - “That the truth consists of hard-to-vary assertions about reality is the most important fact about the physical world. It’s a fact that is itself unseen, yet impossible to vary.” - David Deutsch, _A new way to explain explanation_ (2009 TED Talk) [16:13]
David's video jarred me into the reality of how hooked I am on entertaining communication. A dearth of chuckles, zero tricks and not one metanoic moment created so much inner head noise I could hardly hear what he was saying. Regardless, I really appreciate the ideas and concepts. Thanks David & TED!
The clarity of a well trained critical thinker, is mostly based on a good inner Ego control. If you can learn to accept you know soo little since you can see so little with your inmediate senses, you will start to use a more disciplined and critical way of analysizing the reality around you hence training your mind to work coherently.
Absolutely brilliant ideas. His test of easy variability of explanation is what I have been looking for to balance the yin of empiricism. Empiricism is like utilitarianism: it sounds perfect and complete, yet you suspect there is something missing there.
Yep, still alive, I do not remember watching this video though. Utilitarianism, you say? I would say that once you realise how difficult it is to define happiness, you see it isn't worth much as a philosophy. @@EmperorsNewWardrobe
This guy spent most of the second half of the video re-discovering Ockham's Razor. The purpose of Ockham's Razor is to cut out excessive explanation that isn't crucial to the observed phenomena. Contrary to popularization, Ockham's Razor doesn't simply state that "the simplest explanation is the correct one." Instead, it states that you should only infer as far as the evidence takes you; no further.
Deutsch would say, “by the application of the idea to achieve rapid progress.” Is that a catch 22? Rapid progress will be made when these ideas spread. But the ideas will spread when their application achieves rapid progress.
He was using the example of how our ancestors attempted to explain the season cycle (Persephone and Hades, etc) as a metaphor for how we today, including today's scientists, attempt to explain things away with untestable & easily variable theories, and why these kinds of explanations should be avoided if we are to continue to rapidly make progress as a species.
Ever since my interest in quantum computer articles by David Deutsch, I think he deserves kudos for the effort he takes to explain his principles to the ignorant...
I think that's kind of what he's saying though. He talks about how people didn't spend much time thinking about things like the stars or other interesting phenomena and people usually accepted dogmatic truths because you would be treated as an outcast or worse for not accepting them. There was great curiousity, but a great deal of resistance - just as you say.
I generally like Ted Talks and think Dr Deutsch is fanatastic, but they really should have rolled a podium out for this speaker, to hold his notes. It would have been less distracting for him and the viewer.
An elegant explanation of how to test the robustness of scientific explanations. I'd be interested in how to *measure* how hard something is to vary. Is there an objective calculation one can make?
I imagine by way of counterfactual of each variable. You take the explanatory hypothesis, and word by word imagine what happens if you remove each one. Does the explanation at any point stop explaining what it purports to explain?
So in other words, creating theories in which every detail plays a vital and functional role in the process that's supposed to explain a phenomenon. That's pretty cool. Nice talk :D
I remember when my friend would explain how Santa Clause exists by adding more magical powers to his arsenal. "He CAN get into houses with no chimneys because he turns into fairy dust and blows under the door crack!" That's still a pretty darn good theory!
@JohnHasSeriousQ : Something that always strikes me about epistemology is the way that the philosophical points one can make about it are often mirrored by technical arguments and constructions in the field of statistics. In this case, the point about 'hard to vary' making for better explanations than 'easy to vary' is analogous to Akaike's Information Criterion and the theory surrounding it.
@neoaeonian Hard-to-vary means that it would be hard to change the explanation without introducing arbitrary bits, or making it contradict the evidence.
I agree, and if you love the tying-into-itself factor, I urge you to read his first book, Fabric of Reality, it has that to the nth degree, it's pure brilliance. His books are my favorite general-audience science books along with the Origin.
I like listening to this man. Although it took a while for him to reach his point, I was captivated by what he was saying. I also like the way he makes controversial statements and doesn't mitigate them by saying things like "I personally think that. . ."
That's exactly right. I just never thought of it in terms of the most important element in scientific understanding. We're always taught that it's thing's like falsifiability which I guess is very much related to this but not the same; and empiricism. I like how he illustrated the points even if the idea was already coined by an early logician.
I found it easier, because he talks slow :) but the point was that "hard to vary" explanations are truthful, because not only are they testable, but, they follow logically (he didn't mention "logic" but that's what I inferred).
johnAshpool... I did notice that too. It's remarkable. Have you seen his hour long talk on Vimeo? Google "Deutsch optimism vimeo" to find it. I didn't notice any mistakes in that talk either. Amazing...
Everything David is talking about are commonly held understandings and all of these ideas, we typically entertain as seperate learnings, can be found one by one right here on the net. Go to, "What the Bleep Do We Know" for a great outline of this stuff. David's actual discourse is based on how wrong we can be on what we think we know. It is amazing how flawed we really are in assembling a complete picture of the universe and all the dimensions adjacent to it.
You can go even further than stating "explanation" and put it down to "frequency and correlation". There is a measured frequency and variable correlation that is tied to both the rotation of the earth it's tilt and the years progressions (etc) that have measurable effects on seasons. This is where the value in a testable claim often is.
@ShadowShorts, if you wish. I cannot help but disagree with pretty much all your points again. I do not think this is inherently negative, I do not believe a War only had one winner (could be nobody, could be both parties, who said War is always a non-zero-sum event?) I *am* an extremist, but not a religious one. Religion is defined as a belief in the supernatural, there's nothing in there about forcing your views onto others. Even though I have strong personal views, I'm a secularist at heart.
Is it wrong to think, in regards to what was said at the beginning of the video about mans progress before the scientific rev., that it could have been like acceleration, in that we advance with a constand acceleration, so your velocity has constantly increased. so there was energy behind or advancements it just took time for there to be a very visible rate of development?
Not wrong, no, but the other implied lesson is that too few people keep up with the process of learning & searching. If more people thought more deeply about ‘what else has to be true for this to be true’, we’d be in better shape by now than we presently are….
If we know that the ratio between the diameter (or, as a derivative of diameter, the radius) and the circumference of a circle is irrational, why sticking to that ratio, as opposed to finding a constant that does have its constant and real inverse value?
* progress depended on learning how to reject authorities. * enlightenment - a revolution in how people sought knowledge. * "Take no one's word for it". * "All observation is theory laden" - Karl Popper. * All knowledge is conjectural. * explanation is a assertion about what's there, unseen, that accounts for what's seen. * Bad explanation - easy to vary. * Good explanation - hard to vary. * the search for hard to vary explanations is the origin of all progress. * Two false approaches blight progress: 1. untestable theories and 2. explanation less theories. * The truth consists of hard-to-vary assertions about reality is the most important fact about the world.
If we would have arisen "a bit" later we would not have seen other galaxies and our cosmological theories would've been very different. Perhaps we're too late to really understand how life got started. All evidence is wiped clean. Also there's the theory that early bacteria came from space, which I think is a superfluous hypothesis. Since we can create amino acids from mixing various atoms together, and that it is what we're mostly made of -- makes evolution feel inevitable.
No, you've all got it wrong. I think what he was saying is that understanding is vastly different from experience. One requires observation the other requires both observation and reason...
Basically what this dude is explaining is that "tout les modèles sont faux, mais certains sont utiles". Le mondel est un médium qui connecte le monde des idées au monde physique de sorte à expliquer la prédictablilité des événements. "Truth" is the most accurate model to predict what it is intended to predict.
what he means by "varied" is rationalized an explanation is easy to vary" When it can wrap it's way around any outcome, i.e. can rationalize with any and all new evidence its really the same thing as unfalsifiability
I do not disagree with David's presentation. I only wish to make one qualification with respect to myths. Myths are only myths in retrospect. At the time of their creation they were the best science of their day. We didn't go from 100,000 years of being myth based to a sudden explosion in scientific thinking and discovery. We always operated on truth being "correspondence with the facts".
+David Lilley I had a computer problem but now I am able to finish my comment. We have had three enlightenments on top of those that China provided long before ours. Our first was 2,400 years ago with the Greeks. You only have to look at Bertram Russell's awe of this period to understand that it was a bigger jump forward in relative terms than the Enlightenment. Our second enlightenment was the 500 year Islamic Golden Age, translating the Greek knowledge and other knowledge, preserving the Greek knowledge and standing on their shoulders and delivering new knowledge. Only to stop abruptly in 1,100 AD and deliver nothing since. The Enlightenment was the third enlightenment. And, like the Islamic Golden Age, it relied heavily on the Greek golden age and especially their preservation of Greek knowledge. My bottom line is that (1) we have had enlightenments before and failed to build on them and (2) science (trial and error) is not new but as old as mankind. The only impediment to scientific progress is when we think we know it all.
I have to take exception with your assertion that science is as old as mankind. This is just fundamentally untrue. The methodology of science is a prosthetic to correct for the human frailty of mind that prevented genuine discovery. This is why human technology remained essentially unchanged aside from some accidental advances. Also Islam was the reason Islamic golden age came so completely to an end. Islam is antithetical to science and reason as are most other religions, but it is even worse.
I agree with one exception. Popper gave us P1, TS, EE, P2 repeat in Objective Knowledge. He puts it simply "we learn by trial and error". We start with a problem (P1) rather than on observation or something we thought up in an oven (Descartes), we come up with a trial solution (TS) and test it (error elimination, EE) which leads to a better understanding of the problem and its porential solution. We reach a new starting point P2 and repeat. Aristotle, the first scientist, had no frailty of thought 2,400 years ago. Science is only about problem solving and we all participate in problem solving every day. Thus I can say that science is as old as mankind, probably as old as our having a neocortex.
David Lilley I need to read more Popper. When I say science I mean the modern methodology that understands and corrects for the psychological problems of confirmation and other biases, hypothesis testing, etc. What's funnier still is human rationality is so frail that most published 'science' isn't rigorous at all, and will eventually be thrown in the dust bin of misinformation along with all the religions. ; )
Science, or what Popper called World 3, objective knowledge, is doing just great. Imagine how many times we went through the P1, TS, EE, P2 routine before we stopped the spread of ebola and we will do the same with the zica virus. My take on religion is that man isn't religious and never has been. In most of western Europe we don't do religion but have NO POSITION wrt an absolute being. Animism was a great idea superseded by a better idea, polytheism, superseded by a better idea, monotheism. Ideas come from thinkers, philosophers and scientists. Any cosmologist trying to understand the world we live in. Our cosmology moves on as we make new discoveries about the world and ourselves. An old cosmology morths into a religion when it refuses to move on because its sponsors and employees have relied on it for a good living. Witness the Vatican, the biggest building in every UK town and village and the biggest house in every town and village.
I thought this was a great talk, but I don't know how fully I agree. If the sun revolved around the earth & wasn't in line with the equator it would theoretically have the same effect on the seasons (though obviously other issues would come up) A holistic theory that fits w/ everything else 'proven'--as long as you begin with a correct original theory--will more likely be correct. That's what I thought the title was pointing to- the ability to "prove" & then explain that wisdom for posterity.
and what about those assertions which only seem to be impossible to vary for us? i mean, if we were smarter, we could realize they are not so unique after all.
While I like what Dr. Deutsch has to say - I think he's quite mistaken about the relative stagnation of human progress in early human history. That kind of a view is what a scientist steeped in scientific myth tends to display. The ancient man had little time to spend theorizing about stars simply because he had a more pressing concern - staying alive both from predators as well as other human beings. The space that scientists have - that luxury - to question authority was built on the backs of those who obeyed authority in the service of figuring out first how to treat each other. In contrast, post enlightenment - well within the context of exponential knowledge growth with accompanied search for right explanations for phenomena, the world barely managed to pull back from the precipice of total annihilation several times. In other words, the depraved behavior of man even with the "right" explanations and the "right" methods of eliciting truth has balanced us on the knife edge of destruction and utopia. The irony is that had stone age men availed themselves of the scientific method at that time - we might have never made it thus far.
@@mlonyenioner Heh - aren't you the one calling them cave paintings? As if it was a recreational activity? It could just as well be a nursery or a school rather than something purely creative past time. You're just injecting your theory into the past. They did have time for theorizing - we call it myth at the moment.
@@ajsirch I'm not injecting anything. You said they didn't have time for theorizing, I point out that they had time to make cave paintings. Now you're saying they had time for theorizing. Great, we agree.
@@mlonyenionerIt's well and good you found an explanation that works for you. Myths create a level of explanation that "works" - in the "who" and "why" sense, not in the "how" sense. As long as "how" remains low on the demand for explanation - earlier societies were able to deal with their existential issues. It's only when "how" questions made their way front and center, that significant time and resources were devoted to it on the hope/faith that it would payoff even in existential matters. Their faith was rewarded not only with extraordinary development but also with equally extraordinary destructive capabilities. But you have your explanation -
@@ajsirch I agree that myths are not good explanations, but they are explanations and they come from theorizing. You said that early man did not have time for theorizing, but obviously they did. I fail to understand what you are trying to get at with your existentialist spiel. I am sure early man were just as unable to deal with existential issues as we are.
yes but those confidence levels are based on evidence interpreted with a different presupposition then creationist would use. And that's ok because based on a creationist interpretation the stats would be flipped. A creationist could claim the same amount of validation using their presupposition. The problem here is that evolutionist refuse to admit their presuppositions where creationist don't (or at least shouldn't). Karl Popper would say it was very bold for such claims of certainty.
+Plantastic Life These are really two ways of saying the same thing. However, he could have used the age old definition of truth "correspondence with the facts" that has more recently been given logical proof by Tarski. But all three statements are essentially the same.
+Plantastic Life No. Its possible to have a theory that is consistent with all the evidence but is false. He also said that truth "consists of", and not "is accounted for by".
In the way that the most common denominator in all of science and progress are the establishments that make it possible for it to take manifest in the first place. Even the most basic and first of the modern (so not stone-age) scientific progressions in the history of man has been made possibly by, often but not always, some form of government or upholding of a social contract by a bigger establishment. Where I disagree with him is in his argument that all establishments bar progress.
ShadowShorts: "I hesitate to reply to someone who immediately marginalizes my remarks" I didn't mean to marginalize, sorry if that's how it looked. I was merely voicing disagreement. ShadowShorts: ""ignorance is bliss." That may be the case for uncomfortable personal truths, but I don't believe it applies to -what we would call- scientific truths.
Seems wrong, at least when phrased like that. It is seems that under favourable conditions at least some new technologies were made and preserved over time so that the space of possible new technologies (that require prior advances) became larger. But it may also be said that this process can be slowed down, halted, or even reversed at least in a region (without knowledge transfer global) under unfavourable conditions. (strict (autocratic) conservative regimes, theocracies, ludistic movements)
When less and less people was imprisoned by religion we could suddenly make the scientific leap forward. Thats why science and progress in all areas have literally exploded. Without religion we probably had developed much faster and as we can see, more and more people abandon religion and old myths to explain the world, and thank God for that ;))
@3877michael Religion is about how to live your life. Science is about life as a phenomena. Two totally different things. Trying to choose one over the other or merging them is useless.
