The Beginning of Infinity, Part 1

welcome to the eponymous novel podcast the main topic that we started out on was timeless principles of wealth creation and then we've been touching a little bit on internal happiness and peace and well-being but i am first and foremost a student of science and failed physicist if you will i loved physics i wanted to pursue it but i never felt i was going to be great at it and i was pulled into more technology which is applied science nevertheless i've remained a student of science i remain fascinated by it and all of my real heroes are scientists because i believe that science is the engine that pulls

humanity forward i've been lucky to live in an age where scientific progress and technological progress seem not likely but inevitable so we've gotten used to this idea that life always gets better despite all the complaining that goes on about how productivity growth is stagnant the reality is anyone who owns a smartphone or drives a car or even lives in a house has seen technology improve their quality of life over and over again we take this progress for granted and it's thanks to science so i continue to

be fascinated by science and to me science is also the study of truth what do we know to be true how do we know something to be true and as i get older i find myself incapable of having attention span for anything which is not steeped in truth so the background on this particular podcast series is i thought i knew a lot about science and there was a lot about science that i took for granted such as what scientific theory is and how scientific theories are formed most of us have a vague idea of it and it can range from some people think science is what scientists do

which has a definitional problem as in what is a scientist and other people think well science is making falsifiable or testable predictions and maybe that's closer to it and then sometimes people say what's the scientific method and what is the scientific method and then they start describing their junior high school chemistry experiment and lose the trail after that especially in these days where we're told to quote unquote believe in science which is an oxymoron people respect science but they don't

understand what science is the idea of what science is is getting hijacked sometimes by well-meaning people who want to convince you of the science and sometimes by not so well-meaning people who just want to influence the way that you think and feel and act i was very pleasantly surprised a couple of years back that i reopened an old book which i had read or i thought i'd read about a decade ago called the beginning of infinity by david deutsch sometimes you read a book and it makes a difference right away sometimes you read a book and you don't

understand it then you read it later at the right time and it makes a difference this time when i reopened this book and i went through it much more carefully than i had in the past meticulously rather than reading it to read it and to say i was done reading it i read it to understand the concepts and the topics and stopped at every point where something was new it completely started reforming my worldview it changed the way that i think and i would credit this book as being probably the only book in the last decade except maybe a few of nasim teleb's works and

maybe one or two other scatter books that i feel made me smarter they literally expanded the way that i think they expanded not just the repertoire of my knowledge but the repertoire of my reasoning people throw around words like mental models a lot and i find most mental models not worth reading or thinking about or listening to because i find them trivial however the mental models that came out of the beginning of infinity are transformational because they very convincingly completely change the way that you look at what is true and what is not

karl popper laid out the theory of what is scientific and what is not what is a good explanation what is not and what deutsch does is he expands on that dramatically in the beginning of infinity but even that is to do it a disservice the wide-ranging nature of what he covers in the beginning of infinity is incredible he goes from the theory of knowledge which goes by the fancy word epistemology all the way to quantum mechanics and physics and multiverse theory to infinity and mathematics to the reach of what is noble and what is not noble universal explanations the theory of

computation what is beauty what systems of politics works better how to raise your children these are all encompassing long-range philosophical ideas the beginning of infinity is not an easy book to read to some level deutsche could not but write for other physicists he has a certain peer group that he respects and who respect him and he has to meet them at their level so he has to write for other physicists and philosophers part of what i wanted to do was i wanted to understand these principles in the book

verify confirm them for myself or not i love the old motto from the royal society which says nullius and verba which says take no one's word for it in other words figure it out yourself that's the only way you know anything so i wanted to confirm the principles in the beginning of infinity or to refute them for myself so to do that i was reading and rereading the book i started reading some blog posts on it and then eventually i found a guy online named brett hall and i started listening to his podcast which was called talk cast but tok cast

for the theory of knowledge cast and brett i'm going to let you introduce yourself but i would say that listening to your podcast has helped me clarify a lot of these principles and i would love to have you talk with me so that we can both understand the depth the clarity the reach the importance of these ideas and then hopefully someone else out there can become smarter by it hello naval and it's great to be here you've raised so many interesting aspects of the beginning of infinity which has become a real passion of mine

like many people who enter into science when i was at school i thought well i want to be an astronomer when i enter university i want to go and do a physics degree do an astronomy degree and then become a professional astronomer it wasn't until one day i was in a bookstore and i found this book called the fabric of reality by david deutsch and i started reading it and the first chapter described what i was trying to achieve in my life it was putting into words what i felt my university studies what my

general outlook on life was about because david deutsch says there the ancient philosophers thought that they could get an understanding of the entire world and then later on as time passed modern science made it seem as though this was an impossible project there's no way you could understand everything about reality there's too much to know how could you possibly know everything david deutsch presents at the beginning of the fabric of reality this idea that you don't need to know absolutely every single fact

that needs to be known in order to understand fundamentally everything that can be understood he was presenting this vision there are certain fundamental theories in science and outside of science and his four theories that he had were quantum theory the theory of computation the theory of epistemology and evolution by natural selection that these together formed a world view a lens through which you could understand anything that could be understood i saw a beautiful video with him on youtube where he was making the same

points where he was saying you don't have to memorize and know every fact you don't have to know where every particle moved but if you understand the deep underlying theories behind everything then you know at a high level how everything works and this can all be understood by a single person a single brain a single human being it's accessible to anybody and that is a jaw-droppingly powerful idea we can have explanations that can reach the entire universe and it's worth going through the four

that you'd mentioned quantum theory is one of them theory of computation is another one of them the theory of evolution is another one of them and then the theory of knowledge or epistemology is the fourth that's the way he presented it in fabric of reality is it interesting that relativity is not in there he regards quantum theory as being deeper than the theory of relativity at some point most physicists expect that we're going to have a unification of quantum theory and relativity it's not to say that in that world view

that we're dismissing relativity but his guess is that quantum theory will be more foundational than what the theory of relativity is there'll be a space time of the multiverse that's why relativity doesn't appear amongst them the beginning of infinity reminds me the most of godalesherbach as a book in that it's very wide-ranging it stitches together ideas from many different disciplines it's very difficult to understand and follow completely everyone claims to have read it but as far as i can tell very few people understand it

i had this experience in college where i first found go to lescherbach and i remember that i put on my bookshelf and i started reading it and started reading it started reading it about a year later i was probably about halfway through it and then i just ran out of time and other things going on and i remember that i would approach my other friends in college and i would say either this is a great book you should read it or i would say have you read it and they'd all say yeah yeah that's great and a week later they'd roll back and say yeah red go to leicester buck it was

great and i felt like the stupidest person in college and it was only years later that i realized nobody has read it as you get older you get more confident in those confessionals where you either say either i didn't read it or i read it at a constant pace and when i encountered something i didn't understand i kept going i went back much later and i still confess to this day i have not read all of god lescherbach but at least at this point i went through and i found the parts that were most interesting to me which were the godel parts and skipped

the ones that were not as interesting to me which were the bach parts and i did read those and i did try and understand them the beginning of infinity is similar everybody has it on their bookshelf in my social circle many claim to have read it but very few have gotten it i do go back to this point that was first eloquently stated on twitter by a character named illa certain where he said i don't want to read all the books i just want to read the best 100 over and over again and i would say that i'm currently stuck

in a loop where at least in science i am only going to read the beginning of infinity and the fabric of reality over and over again until i understand them fully if i had read them 20 years ago i would know a lot more because then i would have chosen the right books and the right authors to read subsequently it's going to be a hard book to follow you should buy a hardcover and electronics so you have both and the audio get in every way possible if you can get through it on the first sitting and understand all the points at a deep level then congratulations but we're hoping to break it down for

you the difference with the beginning of infinity you're getting a world view you're not being given the standard take from physicists about how to understand quantum theory you're not being given the standard take of how to understand knowledge from philosophers and you're certainly not being given the standard take of how to understand mathematics for mathematicians deutsche is qualified in all these areas he's expert in all these areas so the world view itself what's at the core of it deutsche's world view is that reality is comprehensible problems are soluble

it's a deeply rationally optimistic worldview it believes in good explanations good scientific explanations and progress progress is inevitable as long as we have these good explanations good explanations have tremendous reach they are acts of creativity humans are problem solvers and can solve all problems all sins and evil are due to a lack of knowledge one can be optimistic about constant progress that's what the title the beginning of infinity refers to that we're the beginning of an infinite series of

progress it's a very optimistic take it believes that we are at home in the universe the universe is ours as a resource to learn about and exploit that material wealth is a set of physical transformations that we can affect that everything that is not forbidden by the laws of physics is eventually possible through knowledge and knowledge creation he also talks about how humans are universal explainers that anything that can be known and understood can be known and understood by human beings in the computation power of a

human system it's all noble it's all noble by humans we're the beginning of an infinity of knowledge and as we understand things using good explanations and we create new theories that are constantly being destroyed and replaced by better ones there's no end point in sight there's no perfection every theory can be falsified and improved that we are on our way to being able to do everything that is not forbidden by the laws of physics what does the transforming is knowledge we can take some raw material that had

no particular use and within that raw material we might find uranium nuclei which then can be used in a nuclear reactor to create energy or bombs we can find within something that for almost the entire geological existence of the earth sat there inert and would have done nothing absent people people are the entities within the universe that create explanations they're able to explain what raw materials might be transformed into now what are they transforming these raw materials

into civilization people creating knowledge end up becoming literally a force of nature if we seek to explain something like the shape of a galaxy or the shape of the star any astrophysicist will give you a story based upon the known laws of physics about how gravity will pull things into spheres how the laws of thermodynamics will cause certain kinds of gas to heat up and expand all of the known laws of physics are sufficient to explain what we see out there in the cosmos but the laws of physics alone will not

be able to explain the appearance of manhattan you have to invoke things other than merely the fundamental laws of physics you need to invoke the existence of people and their capacity to explain the world scientifically philosophically politically because it's all of those things that will come together to explain why we have certain structures like skyscrapers in manhattan this is a profound idea it's an idea that seems to have been overlooked by scientists many of whom have a reductionist idea about

how to explain what we see in our environment they will seek to explain only the natural phenomena that are in our environment of course everyone wants to know how the laws of nature work but if we want to understand how the universe from this point onwards whether it's locally on our own planet eventually the solar system eventually the galaxy is going to evolve over time we're going to have to talk about the knowledge that people create and the choices that they're going to make into the future this is a different

vision of the place of people in the universe stephen hawking famously said people are nothing special people in chemical scum on a very typical planet orbiting an average star in the outer suburbs a very typical galaxy which is one among hundreds of billions of galaxies in the universe this vision of what people are and of what the planet earth is it's true in a trivial sense but it misses the point that in people are a hub of a kind we are so far as we know the sole place

in the universe which is creating knowledge an open-ended stream of knowledge that could transform the rest of reality in the same way that gravity is able to pull that galaxy into a particular shape knowledge in the future will be able to shape the course of the planet the solar system eventually the galaxy we will have this profound impact upon everything that we can see around us and there's nothing that the laws of physics the laws of chemistry or even the laws of biology

can predict what is going to happen in the future the attempt to predict the future growth of knowledge is impossible that's the nature of knowledge because knowledge creation is genuinely an act of creation it is bringing something into existence that wasn't there prior if you could predict it you would have invented it already a lot of our deeply pessimistic world views come from a straight line linear extrapolation of negative trends while ignoring positive trends and positive trends mostly come through

creativity and knowledge creation and it's inherently unpredictable so every generation has this doomsayers and cassandras the modern malthusians who say on this trajectory we're all gonna die they're very popular for the same reason that zombie movies and vampire movies are popular but the reality is that they cannot predict what we're going to do in the future that is going to improve our quality of life and save us from inevitable ruin the value is in the knowledge and the knowledge is inside the observer and the creator in other words the human

it's not inside the thing itself for example oil is useless unless you know how to refine it burn it and use it for combustion information is useless unless there's a brand there to receive it there could be a signal broadcasting english into outer space but if there isn't a creature capable of understanding what that language is how it works and who's conveying it then it's just modulated electromagnetic frequencies that don't mean anything so a lot of the information and a lot of the value is within a particular knowledge bearing entity

as science grows its reach we've gotten to a very reductive science where we break things down to smaller and smaller pieces and then we try and explain things on the basis of that and there is a counter trend in science which is complexity theory where we talk about emergent properties and higher level systems where we're starting to now look at systems as they operate chaotically and unpredictably at a micro level but at a macro level we can make certain statements about them that do have explanatory power so humans are unique in our capability

to understand things there's a phrase that you're going to hear both brett and i use over and over again and that phrase has good explanations good explanations is deutsche's improvement upon the scientific method at the same time it's beyond science it's not just true in science but in all of life we navigate our way through life and we do it successfully by creating good explanations if you take away nothing else try and understand what a good explanation is a good explanation first and foremost is

testifiable falsifiable you can run some experiment in the real world to see if it's true or not stepping back from that it's a creative explanation it looks at something that's going on in the real world and says this is why it's happening it is a creative leap that says this is the underlying explanation for how the thing works for example when i talk to my young kids and we're out watching the sunset i keep telling them is the sun setting is the sun going somewhere is the sun moving or is it maybe we're moving and we're

moving in such a way that it looks like the sun is setting which is the proper explanation because looking at it naively you would think the sun is hurtling across the sky and there goes the sun again going around the earth but that may not be the only explanation there is a completely creative explanation that seems to fly in the face of the obvious observation of the sun's movement but could also fit the facts but it requires some creativity and that creative explanation is that the earth is rotating good explanations don't have to be obvious they're not

derived from just looking at what happened in the past but they are testable there are experiments we can run to figure out is it the sun that is growing around the earth or is it the earth turning brett would you say that a scientific theory is a subset of a good explanation yes they're the testable kinds of good explanations falsifiable theories are actually a dime a dozen this doesn't tell you anything about the quality of the explanation you're being given the example that's used in the fabric of reality is the grass cure for the common

cold if someone comes along to you and says if you eat 1.0 kilograms of grass it will cure your common cold they have a testable theory the problem is that no one should test it why because they haven't given you an explanation as to what the mechanism is that would enable grass to cure the common cold and if you do eat the 1.0 kilograms of grass and it doesn't cure your cold they can turn around and say 1.1 kilograms might do it right or you need a different kind of grass

or you need to always do it on a different day it's always testable but you're not getting anywhere you're not making any progress so i think the second piece of good explanation is hard to vary it has to be very precise and there's a good reason for the precision the famous example he used in the beginning of infinity is the why do we have seasons on the earth and there was the old greek explanation well it's driven by persephone the goddess of spring that's when she can leave hades and there's this whole theory involving gods and goddesses not only was that not easily testable it was very easy to vary persephone could

have been nike and hades could have been jupiter or zeus it's very easy to vary that explanation without the predictions changing whereas if you look at the axis tilt theory of saying the earth is angled at 23 degrees relative to the sun and therefore would expect the sun to rise here in the winter and over there in the summer the facts on that are very hard to vary it makes risky and narrow predictions they can predict the exact length of summer and winter at different latitudes and you can test that very precisely so

beyond it being a creative theory that is testable and falsifiable it should be hard to vary the pieces of that theory without essentially destroying that theory and you certainly don't want to vary it after the fact like your grass example oh it was one kilogram now it's 1.1 now it's 1.2 finally the predictions that it makes should be very narrow and precise and they should be risky for example i believe in relativity was it eddington who did the experiment and showed that star light gets bent around an eclipse and that was a prediction that einstein had made in relativity which turned out

to be true that was a risky prediction that took a long time to confirm that's an excellent example of what's called a crucial test which is sort of the pinnacle of what science is all about if we do a test and it doesn't agree with a particular theory that we have that's problematic but that doesn't mean that it refutes the theory because if you were to refute the only theory that you have where do you jump to you don't have any alternative if we were to do a scientific test tomorrow and it was inconsistent with the theory

of general relativity then what there is no alternative to general relativity in fact when there have been experiments over the years that seem to have been inconsistent with general relativity guess what they've all turned out to be faulty if you had to choose between whether or not general relativity has been refuted by your test or your test is flawed go with the fact that your test is being flawed in the case of eddington's experiment we had two viable theories for what gravity was we had newton's theory of universal gravitation on the one hand

and we had einstein's general theory of relativity on the other this experiment that you described of how much the light was bent during a solar eclipse the correct way of describing what happened is not that we showed that general relativity was correct in some final sense but rather we refuted newton's theory of gravitation newton's theory was ruled out because it was inconsistent with the test while general relativity was consistent with the test this doesn't mean that general relativity is the final word in science it means it is the best

theory we have for now and there's a whole bunch of reasons that we might think general relativity ultimately has to turn out false we never have the final word and that's a good thing that's a really positive optimistic thing because it means we can keep on improving we can keep on making progress and we keep on discovering new things there is no end of science the long thought about idea that so many have feared that one day progress will come to a halt that science will end in fact we are at the beginning of infinity and we will always be at the beginning of infinity

precisely because we can improve our ideas because we're fallible human beings so none of our theories are perfect because we aren't and our process by which we create knowledge isn't perfect either it's error-prone there are two other scientific thinkers that i like who are unrelated to david deutsch but come to very similar conclusions one is nasim taleb who's popularized the idea of the black swan which is that no number of white swans disproves the existence of a black swan you can never conclusively say all swans are white you can never establish final truth all you can do is

work with the best explanation you have today which is still better than ignorance far better but at any time a black swan can show up and disprove your theory and then you have to go find a better one the other fellow who i find fascinating is gregory chaitan he is a mathematician who is very much in the curt girdle vein where he tries to explore the limits and boundaries of what is possible in mathematics one of the points that he makes is that godel's incompleteness theorem doesn't say that mathematics is junk

it's not a cause for despair gordo's incompleteness theorem says that no formal system including mathematics it can be both complete and correct either there are statements that are true that cannot be proven true in the system or there will be a contradiction somewhere inside the system so this could be a cause of despair for mathematicians who view mathematics as this abstract perfect fully self-contained thing but chetan makes the argument that actually it opens up for creativity in mathematics it means that even in mathematics

you are always one step away from falsifying something and then finding a better explanation for it it puts humans and their creativity and their ability to find good explanations back at the core of it at some deep level mathematics is still an art there's very useful things that come out of mathematics and you're still building an edifice of knowledge but there is no such thing as conclusive settled truth there is no subtle science there is no settled mathematics there are good explanations that will be replaced over time with more good explanations that explain more of the world

this is something that we inherit from our schooling more than anything else it's part of our academic culture and breeds into the wider culture as well people have this idea that mathematics is this pristine area of knowledge where what has proved to be true is certainly true then you have science which doesn't give you certain truth but you can be highly confident in what you discover you can use experiments to confirm that what you're saying appears to be correct but you might be wrong and then of course there's philosophy which is a mere matter of opinion

this is the hierarchy that some people inherit from school mathematics are certain science is almost certain and the rest of it is more or less a matter of opinion this is what deutsch calls the mathematician's misconception is that mathematicians have this intuitive way of realizing that their proof their theorem that they've reached by this method of proof is absolutely certainly true in fact it's a confusion between the subject matter and our knowledge of the subject matter if i quickly compare it to physics we

have this domain called particle physics and the deepest theory we have in particle physics is called the standard model which describes all of the different fundamental particles that there are and the interactions between these fundamental particles the forces that exist between them and the gauge bosons which mediate the force between particles like electrons protons and neutrons now what is matter made of we would say matter is made of these particles the particles described by the standard model of physics

but does that rule out the fact that these fundamental particles might themselves consist of even smaller particles we have this idea of string theory so our knowledge of what the most fundamental particles are and what in reality the most fundamental particles are is different so too in mathematics deutsche explains that mathematics is a field where what we're trying to uncover is necessary truth the subject matter of mathematics is necessary truth in the same way that the subject matter of particle physics are the fundamental

particles but because the subject matter of fundamental particle physics are the fundamental particles that doesn't mean you actually find the fundamental particles all it means is that you have found the smallest particles that your biggest particle accelerators are able to resolve but if you had an even bigger particle accelerator you might find particles within those particles this has been the history of particle physics by the way we used to think that atoms were fundamental then of course we found that they contain nuclei

and electrons in the nuclei we found out there were protons and neutrons inside the protons and neutrons we found out they were made up of quarks and that's where we're at right now we're at the point where we say that the quarks are fundamental and the electrons are fundamental but that doesn't mean that we're going to end particle physics right now what we need are further theories about what might be inside of those really small particles comparing that to mathematics if necessary truth is the subject matter of mathematics

our knowledge of that necessary truth is what mathematicians are engaged in they're engaged in creating knowledge about necessary truth and because a mathematician has a brain which is a physical object and all physical objects are subject to making errors of degradation via the second law of thermodynamics or simply just the usual mental mistakes and errors that any human being makes a mathematician is just as fallible as anyone else then what they end up proving could be an error so if i understand this

point even mathematics is capable of error because mathematics is a creative act we're never quite done there could have been a mistake in your axiom somewhere ultimately even mathematics is a creative act and can have error within it all knowledge is conjectural it's always being guessed it's our best understanding at any given time you're right to say that the axioms might be incorrect how do we know that an axiom is incorrect traditionally the answer has been because it's clearly and obviously the case how

can you prove that x plus 0 must equal x well you just have to accept that it's true but if we consider something like euclid's elements for example draw two points on a piece of paper now through those two points a unique straight line can be drawn this was accepted as true for centuries when anyone listening might want to try the experiment for themselves take a piece of paper take a pen draw two dots on the piece of paper now how many unique straight lines can you draw

through those two dots it should be fairly obvious to you that only one such line can be drawn however we now know that's false i just want you to reflect as you're staring at the piece of paper through which only one straight line is being drawn you have the feeling of certainty you are absolutely sure that you're not wrong this feeling is something we should always be skeptical of because when people have been absolutely certain even in a domain as apparently full of certainty as mathematics they've

been shown to be wrong so how can we show it wrong here's what you do and you might think that i'm cheating but then again you have to reflect on did you understand what i was saying when i first told you to draw a unique straight line through these two points here's what i want you to do bend the piece of paper think in three dimensions wrap the piece of paper around a basketball if you have one now consider the ways in which you could draw a straight line through those two points you could punch a hole through one of

those dots with your pen and push it out through the other side through the other hole and now you have a different straight line you have the straight line that is drawn with your pen and you have a straight line that is literally your pen that has been pushed through these two dots so your initial feeling of absolute certainty that only a unique line could be drawn through these two dots is false and you might be thinking that's unfair that's cheating you were thinking in two dimensions no you were thinking in two dimensions i wasn't i was thinking of more dimensions than

that karl popper has this wonderful saying it is impossible to speak in such a way that you cannot be misunderstood this is always the case so even in mathematics where we try and be as precise as possible it's possible for people to make errors to think false premises about what the argument is that they're trying to make and by the way this particular example of euclidean geometry because geometry was traditionally always done in two dimensions on a piece of paper was resolved by various people and led to geometry in

curved space which led to einstein coming up with general theory of relativity so it is questioning these deepest assumptions that we have where we think there's no possible way we could be mistaken that leads to true progress to genuine fundamental change in the sciences and everywhere else you said that we went from atoms in the time of democritus down to nuclei and from there to protons and neutrons and then to quarks it's particles all the way down to paraphrase feynman we can keep going forever but it's not quite forever right

at some point you run it into the planck length there's the planck time there's the plank length there's even the plank mass which is actually quite a large mass these things don't have any physical significance it's not like the planck time is the shortest possible time and it's not like the plank length is the shortest possible length the reason for that is because these planck things are part of quantum theory but length is not described by quantum theory it's described by the general theory of

relativity and in that theory space is infinitely divisible there is no smallest possible length or time this illuminates an ancient tension between the discrete and the continuous because quantum theory seems to suggest that things are discrete for example there's a smallest possible particle of gold the gold atom there's a smallest possible particle of electricity the electron there's a smallest possible particle of light the photon in quantum theory we have this idea of discreteness that

there is a smallest possible thing from which everything else is built but in general relativity the idea is the opposite it says things can continuously vary and if the mathematics requires that things be continuously variable so they can be differentiated and so on the idea there is that you can keep on dividing up space and you can keep on dividing up time so physicists understand that there is this contradiction at the deepest level of our most foundational explanations in physics and it's one of the reasons why

there are these attempts to try and unify quantum theory and general relativity because what is the fundamental nature of reality is it that things can be infinitely divisible or is it that we must stop somewhere or other because if it's infinitely divisible then quantum theory might have to be subservient to general relativity but we just don't know there goes my solution for zeno's paradox which is before you can get all the way somewhere you have to get halfway there and before you can get halfway there you have to get a quarter

of the way there and therefore you'll never get there one way to get past that is say even a series of infinite things can have a finite sum just run the infinite series and sum it and we learned pretty early on that converges but another thought i had was that you have to cover a minimum distance a plank length and therefore you will get there it's a finite series of steps but you're saying we just don't know yes so if the laws of physics say that we can cover one meter in a certain time period then that's exactly what we'll do and our current understanding of the

laws of physics say precisely that so zeno's paradox is resolved simply by saying that we can cover this space in this amount of time it's silent on whether or not space is infinitely divisible when someone asks you is space infinitely divisible then i would say yes it is and they might turn around and say how do you know and i would say general relativity how do i know that's true well i don't know that it's true however it is the best explanation that we presently have of space time and then they might get

into a discussion about well if it's infinitely divisible then you're presented with xenos paradox all over again and i would say no you refute that by a simple experiment so we don't know how it is that we can travel through all of these infinite points if in fact there are infinite points xeno's paradox is about the domain of pure mathematics but we don't live in a world of pure mathematics we live in a world of physics and if the physics says that we can transverse an infinite number of points in a finite amount of time

then that's what we'll do regardless of what the mathematics is every mathematical theory is held inside a physical substrate of a brain or a computer you're always bound by the laws of physics and these pure abstract domains may have no mapping to reality the overwhelming majority of theorems in mathematics are theorems that we cannot possibly prove this is girdle's theorem and it also comes out of turing's proof of what is and is not computable these things that are not computable vastly outnumber the things that are computable and

what is computable depends entirely upon what computers we can make in this physical universe the computers that we can make must obey our laws of physics if the laws of physics were different then we'd be able to prove different sorts of mathematics and this is another part of the mathematician's misconception they think they can get outside of the laws of physics however their brain is just a physical computer their brain must obey the laws of physics if they existed in a universe with different laws of physics then they could prove different theorems

but we exist in the universe that we're in and so we're bound by a whole bunch of things not least of which is the finite speed of light so there could be certain things out there in abstract space which we would be able to come to a more full understanding of if we could get outside of the restrictions of the laws of physics here happily none of those theorems that we cannot prove at the moment are inherently interesting some things can be inherently boring namely all of these theorems which we cannot possibly prove as true or false those theorems can't have any bearing in

our physical universe they have nothing to do with our physical universe and this is why we say they're inherently uninteresting and there's a lot of inherently uninteresting things does probability actually exist in the physical universe or is it a function of our ignorance if i'm rolling a dice i don't know which way it's going to land so therefore i put in a probability but does that mean that there's an actual probabilistic unknowable thing in the universe is the universe flipping a coin somewhere or is it always deterministic all probability

is actually subjective uncertainty and randomness are subjective if you don't know what the outcome's going to be so you roll a dice that's because you individually do not know it's not because there is uncertainty there deeply in the universe what we know about quantum theory is that all physically possible things occur this leads to the concept of the multiverse and rather than refute all of the failed ways of trying to understand quantum theory we're just going to take

seriously what the equations of quantum theory say what we are compelled to think about quantum theory given the experiments is that every single possible thing that can happen does happen this means that there is no inherent uncertainty in the universe because everything that can happen actually will happen it's not like some things will happen and won't happen everything happens now you occupy a single universe and in that universe when you roll the dice it comes up a two but we know somewhere else in physical reality it comes up a

one somewhere else three a four a five and a six if i'm rolling two dice then the universe in which they sum up to two is less than the number of universes in which we roll a seven because that can be three or four or five and a two and so on so the number of universes still does correspond to what we calculate as the probability yes this leads to what deutsch calls the decision theoretic way of understanding probability within quantum theory decision theoretic means you assume this proportionality between the universe is

this way of splitting things up so if you're rolling two different dice then the universes proportion themselves into measures and what a measure is is it's a way of talking about infinities there is a video on youtube which has deutsche explained the famous quantum double slit experiment which is about particle wave duality is light a particle or a wave you pass it through a slit depending on whether there's observer and interference or not it ends up in a wave pattern ends up as individual photons and this is the famous experiment which

has baffled people for a long time and caused them to revise their world view the one that led einstein to say god does not play dice with the universe correct einstein was a realist at the time when the founders of quantum theory were trying to develop a good explanation of what precisely was going on with these experiments in quantum theory einstein rejected all of them on the basis that they weren't realistic and he was right to do so because none of them made any sense and to this day none of the other alternatives make any sense now einstein

didn't know about the multiverse we had to wait until hugh everett in the 1950s was able to devise a simple realistic way of understanding quantum theory but if i go back to this idea of the double state experiment it is often claimed that particles have a duality to them sometimes they're particles and sometimes they're waves the electron for example given certain experiments will behave like a particle and in other experiments it behaves like a wave people who hear this think well okay that kind of explains what's going on for example

in the photoelectric effect you shine a light at electrons which literally means you're firing a photon a particle of light at an electron and you can knock the electron out of the atom this is supposed to be proof positive that light in the form of photons and electricity in the form of electrons are both particles because they're bouncing off one another and this is what particles do waves don't do that you watch water waves at the beach you'll see they pass through each other they don't bounce off one another waves will bounce off particles but they

won't bounce off each other prior to young's twin slit experiment we actually relied upon newton's ideas of light and newton's idea was that light was corpuscular as he said which means made of particles and then young came along and he shone a light through two slits cut into a piece of paper and what you find when you project that light onto another sheet of paper is not just two beams of light you find what's called an interference pattern where the light has interfered with itself in the same way that when

waves pass through small apertures natural geological gaps they will interfere with one another they produce crests in some places and troughs in others they can cancel each other out this was supposed to be proof to some of the early physicists that light in fact was a wave and now we get to quantum theory and we find that things we thought were certainly particles like electrons when we do the same experiment with them they interfere with one another so it appears as though we've got particles acting like waves and waves

acting like particles the resolution to this is not to admit nonsense so this is what often is explained in quantum theory lectures in undergraduate level is that you have to accept that something like a photon is born as a particle it lives as a wave and then it dies again as a particle which is nonsense and the reason it's nonsense is because the photon doesn't know that it's alive and it's dead it doesn't know what experiment it's participating in so we have to come to a deeper understanding of how to explain what is going on in this double-slit experiment because

if we fire either a photon or an electron at that double slit apparatus and we put a detector at either of those slits then we will detect a particle so we can detect that we fired a particle we can detect that a particle is going through those slits and we can detect a particle at the projection screen as well when you do this experiment in the laboratory using electrons you can see the dots where the electrons strike hitting the screen but you don't get a simple pattern that you would expect if you're firing cannon balls

at a wall where there are two holes in the wall through which the cannonballs can go you would expect that all the cannonballs are going to go through those two holes and land in one of two positions behind the wall but with particles at the quantum level that's not what happens something is going on and the only explanation is that when we fire a photon there's the photon that we can see in our universe but there's also photons in other universes passing through the apparatus that we

cannot see and these photons are able to interact with the photon that we are able to detect this is where the concept of interference comes in interference is an old concept in physics it goes back to waves waves certainly interfere but we need to understand the way in which particles can interfere one with another particles that we can observe and particles that we can only assume to observe given these experiments and this is why we are forced into acknowledging the existence of

these other particles and not only these other particles but other universes in which these particles exist now people might object at this point and go how dare you invoke in science things that cannot be seen things that cannot be observed this is completely antagonistic towards the scientific method surely and i'll say to anyone who's thinking that right now almost everything of interest that you know about science is about the unobserved let's consider dinosaurs dinosaurs are unobserved

you say oh hold on i've been to the museum i've seen a dinosaur now you have seen a fossil and a fossil isn't even a bone it's an ossified bone it has been metamorphised into rock so no one has ever seen a dinosaur we have seen things that look like dinosaurs and interpreted them to be huge reptilian bird-like creatures that when we assemble their skeletons we make up a story about what this thing was that walked the earth tens or hundreds of millions of years ago in the same way no one has ever seen the core of the sun

and no one will ever observe the core of the sun but we know about stellar fusion we know that hydrogen nuclei are being crushed together there to form helium in the process producing heat we don't see the big bang we don't see the movement of continents almost everything of interest in science we do not observe even many of the things that we say we have seen we've actually just seen instruments detect those things so we're watching the effects through instruments and then theorizing that there are other universes out there where the photons are interacting with

the photons that we can see there are many scientists philosophers have talked about this concept of a multiverse but this is a very strict very sober understanding of what a multiverse is all of these universes in this multiverse obey the same laws of physics we're not talking about universes where there are other laws of physics this should be no more surprising than historically when it used to be thought to be the universe consisted of our planet and around our planet orbited everything else other planets stars the sun the moon orbited around us

existed on this tiny planet then our vision of reality got expanded a little bit we realized in fact we were not at the center of the universe the sun was at the center and these other planets were in fact bigger in some cases in the case of jupiter and saturn and the gas giants bigger than what our planet of earth is the sun was a lot bigger than what we are so our universe became larger then we realized that we were just one star system among many in a huge galaxy of hundreds of billions of stars then later we realized that this galaxy

is one of hundreds of billions of galaxies so the history of ideas and the history of science is a history of us broadening our vision of exactly how large physical reality is and this is another step in that general trend and we should expect it to continue it shouldn't be that hard for people to accept that this is the way to understand things do we know everything about quantum theory and how this multiverse works no we haven't united this multiverse with general relativity we need a space time or a geometry of the multiverse

which we don't have yet so getting back to good explanations where do these explanations come from there's currently an obsession with induction induction being the idea that you can predict the future from the past you can say i saw one then two then three then four then five so therefore next must be six seven eight nine there's a belief that this is how new knowledge is created this is how scientific theories are formed and this is how we can make good explanations about the universe what's wrong with induction and where does new knowledge

come from you did mention the black swan earlier and i'd like to go back to that the black swan is an example that various people have used over the years in order to illustrate this idea that repeatedly observing the same phenomena over and again should not make you confident that it will continue in the future in europe we have white swan so any biologist who's interested in birds be observing white swan after white swan and apparently concluding on that basis that therefore all swans are white then someone travels to western

australia and there you notice that there are swans that otherwise look identical to the ones in europe but they're black let's consider another example of induction ever since the beginning of your life you have observed that the sun has risen does this mean that scientifically you should conclude the sun will rise tomorrow and rise every day after that this is not what science is about science is not about cataloging a history of events that have occurred in the past and presuming they're going to occur again in the future science is an

explanatory framework it's an error correcting mechanism it's not ever of the form the sun always rose in the past therefore arise in the future there's all sorts of ways in which we can imagine the sun won't rise tomorrow all you need to do is to take a trip to antarctica and there for some months of the year the sun doesn't rise at all if you go to the international space station you won't see the sun rise once per day and set once per day it will rise and set repeatedly over the course of your very fast journey around the earth there's another example from science

like this on a heat source put a beaker of water then put a thermometer into that water and turn on your heat source then record as the time passes what the temperature of the water is you will notice that the temperature of the water will increase you can do this with a saucepan at home so long as the heat source is relatively constant the temperature rise will be relatively constant as well so after one minute the temperature might go from 20 degrees celsius to 30 degrees celsius imagine every minute it climbs by another 10 degrees celsius but at some

point it's going to stall when it hits the boiling point precisely now if you're a thoroughgoing inductivist or even a bayesian reasoner and you don't know anything about the boiling temperature and what phenomena happens at that temperature you can join all of those lovely lines into a perfectly diagonal straight line and extrapolate off into infinity after two hours according to your bayesian reasoning according to your induction we should assume that the temperature of that water will be a thousand degrees celsius

but of course this is completely false what actually happens is once it starts boiling it stays at its boiling temperature we get a plateau and this plateau of temperature about 100 degrees celsius remains there until all the water boils away now there's no possible way of knowing this without first doing the experiment or having already guessed via some explanatory means what was going to happen no method of recording all of these data points and extrapolating off into the future could ever have given you the correct

answer the correct answer can only come from creativity and notice that science is not about predicting where the trend starts and where the trend goes in fact if we want to explain what's going on with the water we refer to the particles and how as the temperature increases the kinetic energy of the particles starts to increase which means the velocity of the particle starts to increase eventually those particles in the liquid state achieve escape velocity from the rest of the liquid at this

point we have boiling but that escape velocity the technical term is latent heat requires energy and for this reason we can have heating of something like water without any temperature increase that's what science is that whole complicated story about how the particles are moving faster this invocation of the term latent heat it's not about trends and predictions it's about explanation only once we have the explanation can we in fact make the prediction going even further it's not just science

when we look at innovation and technology and building for example everything that thomas edison did and nikola tesla did these were from trial and error which is creative guesses and trying things out if you look at how evolution works through variation and then natural selection where it tries a lot of random mutations and it filters out the ones that didn't work so this seems to be a general model through which all complex systems improve themselves over time they make bold guesses and then they weed out the things that didn't work

things like a beautiful symmetry to it across all knowledge creation it's ultimately an act of creativity we don't know where it comes from and it's not just a mechanical extrapolation of observations the most famous example on this we mentioned black swans we talked about boiling water but the fun and easy one is the turkey you could have a turkey that's being fed very well every single day and fattened up and it thinks that it belongs and lives in a benevolent household where the farmer comes and feeds it every day until thanksgiving arrives and then it's in for a very rude

awakening or i should say an ending that shows you the limits of induction precisely the theories have to be guessed and all of our great scientists have always made noises similar to this it's only the philosophers or certain mathematicians who think that this is the way that science happens that it's this inductive trend seeking way of extrapolating from past observations into the future einstein said that he wasn't necessarily brighter than most other people it's that he was passionately interested in particular problems and he had a

curiosity and an imagination imagination was key for him he needed to imagine what could possibly explain these things he wasn't looking at past phenomena in order to come up with general relativity he was seeking to explain certain problems that existed in physics induction wasn't a part of it good explanations rely on creativity these good explanations testable and falsifiable of course but they are hard to vary and they make risky and narrow predictions that's a good guiding point for anybody who is listening to this

podcast and trying to figure out how they can incorporate this in their everyday life your best theories are going to be creative guesses not simple extrapolations i had a bunch of asides that i wanted to dive into like finding path integrals because it seems to me that there's some kind of a deep symmetry between multiverse theory and finding path integrals you're absolutely right he believed in multiple histories but to the extent that he thought that these were actually physically real things or merely

mathematical objects is open to question he was relatively silent on the matter he was certainly a realist but he made one of the worst quips and's an absolute genius probably next to einstein second greatest physicists of the 20th century but he said if you think you understand quantum theory you don't understand quantum theory which is nonsense whoever it understood quantum theory david deutsch understands quantum theory so that was one of the few occasions where feynman fell into irrationality and pessimism i think was a plank who said science

advances one funeral at a time yeah unfortunately even the best gets stuck behind i see this in my own field where you have some of the greatest investors of our time like warren buffett and charlie munger who are just absolute geniuses but they cannot wrap their minds around cryptocurrencies the idea that there's going to be an extra sovereign money that is native to the internet is programmable as foreign to them because to them money is always something that has been provided by the government and controlled by the government and they just cannot imagine it any

other way so it's just the nature of people there's also the theory of solomon of induction i'm going to mangle the description but it says if you want to find a theory that explains why something is happening and now a theory here is something that's encoded as a binary string then the correct theory is actually going to be a probability weighted theory that takes into account all the possible theories but weighs them based on their complexity so the simpler ones are more likely to be true and the more complex ones are

less likely to be true and you sum them all together and that's how you figure out the correct probability distribution function for your explanation that's similar to bayesianism isn't it in both cases they're assuming that you can enumerate all the possible theories but you can't because that's the creativity coming in it's very rare in science to have more than one viable theory in physics we mentioned newtonian theory of gravity and there was general relativity that's one of the rare occasions where you actually have these two competing theories

it's almost unknown to have three competing theories what confuses people is that induction and bayesianism work really well for finite constrained spaces that are already known they're not good for new explanations bayesianism is i got new information i used to wait the previous probability predictions that i had now i've changed my probability based on the new data so i believe that something different is going to happen for example i don't know if you remember the monty

hall show monty hall calls you up and there's three doors and there's treasure behind one of them and then two of them don't have anything and you pick which door it's going to be door number one two or three then he opens one of the other two doors and shows you there's nothing behind it now do you want to change your vote the understanding of knife probability says no i wouldn't change my vote why should it matter that one of the ones he showed me doesn't have something the probability should not have changed but bayesianism says you've got new information you should revise your guess

and you should switch the other door and the easier way to say that is imagine there were 100 doors and then you picked one at random then he opens 98 of the remaining 99 shows you there's nothing now do you switch and of course you'd want to switch because what are the odds that you picked one of the 100 in the first place now your odds are 99 out of 100. and people discover this and say of course now i'm a smart bayesian i can update my priors based on new information that's what smart people do and therefore i'm a bayesian

but it in no way helps you discover new knowledge or new explanations that's the uncontroversial use of bayesianism which is a very powerful tool it's used in medicine of trying to figure out which of these medicines might be more effective than others so there are whole areas of mathematics like bayesianism which can be applied in science without controversy at all it's where we say that bayesianism is the way in which we can generate new explanations or the way in which we can judge one explanation against another

in fact the way in which we generate new explanations is creativity in the way in which we judge one explanation against another is either experimental refutation or straightforward criticism of realizing that one of those explanations is just a bad explanation induction also says that prediction is the main reason for the existence of science but it's not it's explanation you want an explanation of what's going on even if you can't necessarily predict with any certainty what's going to happen next in fact knowing what's going to happen next with some degree of certainty can

be deflating and the unknown can be far more fun than having absolute certitude about what tomorrow will bring this brings us to the related point the science has never settled we should always be free to have new creativity a new conjecture you never know where the best ideas are going to come from and you have to take everything that's made in good faith seriously and so this idea that the science is settled or the science is closed is nonsense and it implies that we can all agree upon the process with which we come up with new theories

rather through creativity and conjecture and the door is always open for new people with new ideas to come in and do that as popper said we're all equal in our infinite ignorance so even if someone claims expertise they might even be valid in their claim to expertise there's an infinite number of things they do not know and those infinite number of things they do not know could affect the things they do know so the child who is coming through school who is not expert in anything can still come up with an idea that can challenge the foundations of

the greatest expert because the expert like the child is ignorant about a whole bunch of things they could have error that does not preclude someone else who lacks that fine-tuned knowledge from being able to point out there's an error and here's a better idea a lot of the theories as to why we're imminently going to create an agi are based on a naive extrapolation of computational power it's almost we'll do the induction of more and more computational power and ai has already gotten good at vision and beating us at chess and at video games so therefore it's

going to start thinking soon another offshoot that i want to discuss is this idea that humans are this resource consumers on the earth and we're eating up all the earth's resources so having more humans on the earth is a bad idea whereas if you believe that knowledge comes from creativity then any child born tomorrow could be the next einstein or the next findman and discover something that will change the world forever with creativity that has non-linear outputs and effects but at the moment we're very concerned

about the pollution or the loss of certain species and these are legitimate concerns for some people but it should never be at the expense of the long-term vision that perhaps we can solve all of those problems and far more if only we could have progress at a faster rate by using the resources that we have available to us there's in question why the world always seems to be full of more pessimistic than optimists especially when we still live with mostly enlightenment your values and such tremendous innovation there are probably multiple reasons for

that but it's just easier to be a pessimist than an optimist it's harder to guess how life is going to improve it's easier to linearly extrapolate how it's going to get worse you could also argue that the risk of ruin is so large that you can't come back from it that maybe we're hardwired to be pessimists because if you're correct when you're optimistic then you have a small gain but if you're wrong when you're optimistic and you get eaten by a tiger it goes to zero so maybe we're hardwired to be pessimistic in that sense if you're an academic of some kind then

being able to explain all of the problems that are out there and how dangerous these problems are and why you need funding in order to look at these problems in more depth that appears to be the intellectually serious position someone who claims that we can solve this it sounds a little bit kumbaya even though it's quite right that in fact collaboration cooperation and resource exploitation will actually be the thing that's going to drive this the knowledge economy forward so that we can solve with these problems it always seems more intellectually serious if you can stand up there with a frown on your

face in front of a ted talk audience and say these are all the ways in which we're going to fail and which we're going to come to ruin i'm guilty of having recorded one of these doomsayer podcasts about enders blowing up the earth that was the one podcast that i regretted the most we had a great conversation but i don't fundamentally agree with any of the conclusions that might come out of that which say the world is going to end so we should slow down the only way out is through progress and subsequently i haven't promoted as much as i promoted my other podcast and

upon reading deutsche i realized why it's because it's easy to be a pessimist it's an easy trap to fall into but it implies that humans are not creative it doesn't acknowledge all the ways that we have innovated our way out of previous traps and fundamentally entrepreneurs are inherently optimistic because they get rewarded for being optimistic as you're saying intellectuals get rewarded for being pessimistic so there is always a lot of incentive bias here as an academic you may be incented to be pessimistic as an entrepreneur you may

be incented to be optimistic if you're a pessimist you get your feedback from other people it's a social act you're convincing other people of your pessimism and so far most of their pessimistic predictions have turned out to be false if you look at any timelines on which the world was supposed to end or environmental catastrophes were supposed to happen they've been quite wrong but if you look at the optimistic entrepreneurs they are rated by feedback from nature and free markets which i believe are much more realistic feedback

mechanisms in general professions in which you get your feedback from other members of that profession tend to get corrupted when you see a journalist writing articles to impress other journalists or a restauranteur running a restaurant that's designed to impress other foodies and other restaurateurs those end up not being practical and high quality they may receive accolades and prizes within certain elite circles but they're not reflecting reality where someone who is getting feedback from either mother nature like a scientist or

an experimentalist or from free markets where other people are voting with their money and their time those are going to be much better predictors the people who are operating in the real world and are getting paid for it tend to be optimist the people who are operating ivory towers are incented to be pessimists to be an entrepreneur you need to be optimistic about the fact that you're creating something that other people are going to find value in and people who have a pessimistic philosophy tend to have a pessimistic

psychology as well if you're constantly thinking about all the ways in which the world is going to rack and ruin then this has a day-to-day impact upon your outlook on the rest of society and on your family on your friends on everything because you think that this world is condemned so you're going to feel that weight upon your shoulders and it's going to come through in the way in which you present yourself to the rest of the world we see a lot of this on social media right now entrepreneurs are typically

too busy to spend a whole lot of time on social media but you do get scientists academic journalists who are depressed with life because they have a pessimistic view of reality and that's got to have an impact upon their subjective experience of the world unlike people who are creating trying to bring something new into existence unfortunately the pessimism is self-fulfilling all evils are due to lack of knowledge rational optimism is the way out the data supports it history supports it and we can always come up with good explanations through creativity