Making Sense - Sam Harris - #22 — Surviving the Cosmos

00:00:00.000 welcome to the making sense podcast this is sam harris just a note to say that if you're hearing

00:00:12.520 this you are not currently on our subscriber feed and will only be hearing the first part

00:00:16.900 of this conversation in order to access full episodes of the making sense podcast you'll

00:00:21.800 need to subscribe at sam harris.org there you'll find our private rss feed to add to your favorite

00:00:27.020 podcatcher along with other subscriber only content we don't run ads on the podcast and

00:00:32.500 therefore it's made possible entirely through the support of our subscribers so if you enjoy

00:00:36.540 what we're doing here please consider becoming one

00:00:38.860 today i'm speaking with david deutsch david is a physicist at oxford he's a professor of physics

00:00:53.280 at the center for quantum computation at clarendon laboratory and he works on the quantum theory of

00:01:00.780 computation and information and he is a very famous exponent of the many worlds interpretation of

00:01:07.120 quantum mechanics neither of which do we talk about in this interview david has a a fascinating and

00:01:13.200 capacious mind as you will see and we talk about much of the other material in his most recent book

00:01:19.480 the beginning of infinity and we by no means cover all of its contents but as you'll see david has a

00:01:24.900 talent for expressing scientifically and philosophically revolutionary ideas in very simple language and

00:01:32.260 what you'll hear in this interview is often me struggling to go back and unpack the import of some very

00:01:39.480 simple sounding statements which i know those of you unfamiliar with his work can't parse the way

00:01:46.320 he intends in any case i hope you enjoy meeting david deutsch as much as i did

00:01:51.120 david thank you for coming on the podcast oh thank you very much for having me listen i've been uh

00:02:02.380 i don't know what part of the multiverse we're in where i can complain about uh jihadists by night

00:02:08.400 and talk to you by day but it's a it's a very strange one uh we seem to be in at the moment because

00:02:13.280 we're about to have a very different kind of conversation than uh i've had of late and i

00:02:18.540 really uh have been looking forward to it i spoke to steven pinker uh told him that we were um good

00:02:24.120 to speak and uh he claimed that you are one of his favorite minds on the planet i don't know if you

00:02:28.720 know steven but that's high praise i don't know him personally but but uh that's very kind of him to

00:02:33.140 say that so um let me begin uh quite awkwardly with an apology uh in addition to the apology that i just

00:02:39.880 gave you off air for being late while i aspired to read every word of your book the beginning of

00:02:45.500 infinity before speaking with you i've only read about half not not just the first half i jumped

00:02:49.820 around a bit but forgive me if some of my questions and comments seem to ignore some of the things you

00:02:55.520 had the good sense to write in that book and that i didn't have the good sense to read not much turns

00:03:00.380 on this because as you know you have to make yourself intelligible to our listeners most of whom will

00:03:04.200 not have read any of the book but i i just want to say that it really is a remarkable book i mean

00:03:10.820 both philosophically and scientifically it is incredibly deep while also being extremely

00:03:16.320 accessible thanks and it is a profoundly optimistic book in at least one sense i i don't think i've ever

00:03:23.540 encountered a more hopeful statement of our potential to make progress but one of the consequences

00:03:30.400 of your view if i'm not mistaken is that the future is unpredictable in principle and that the

00:03:36.100 problems we will face are unforeseeable and that the way that we will solve these problems is also

00:03:42.060 unforeseeable and and problems will continue to arise of necessity but problems can be solved

00:03:47.740 and this claim about the solubility of problems with knowledge runs very very deep and it's far

00:03:54.500 deeper than our listeners will understand based on what i've just said so that's a very nice summary

00:03:59.300 it's interesting to think about how to have this conversation because what i want to do is

00:04:03.360 kind of creep up on your central thesis and i think there are certain claims you make claims

00:04:08.980 specifically about the reach and power of human knowledge that are fairly breathtaking and i i find

00:04:15.420 that i want to agree with every word of what you say here because again these claims are so hopeful

00:04:20.960 but i have a few quibbles and and it's interesting to go into this conversation hoping to be relieved of

00:04:26.500 my doubts about your thesis i'm kind of hoping that you'll perform an exorcism on my doubts such as

00:04:32.060 they are sure well i i think the truth really is very positive but i should say at the outset that

00:04:38.120 there is there is one sort of fly in the ointment and that is that because the future is unpredictable

00:04:43.360 nothing is guaranteed uh we there there is no guarantee that civilization will survive or that that

00:04:50.240 our species will survive but there is i think a guarantee that we can and also we know in principle

00:04:57.560 how to before we get into your your claims there let's start the conversation somewhere near

00:05:04.400 epistemological bedrock i'd like to ask you a few questions designed to get to the definitions of

00:05:10.160 certain terms because you use words like knowledge and explanation and even person in novel ways in the

00:05:18.120 book and and i want our listeners to be awake to how much work you're requiring these words to do

00:05:22.260 let's begin with the concept of knowledge what what is knowledge and what is the boundary between

00:05:27.640 knowledge and ignorance in your view yes um so there are there are several different ways of

00:05:34.200 approaching that concept i i think that um the way i i think of knowledge is broader than the usual

00:05:42.980 use of those terms and yet paradoxically closer to the common sense use of the term because uh

00:05:50.840 philosophers have almost defined it out of existence uh knowledge is a kind of information that's the

00:05:58.600 the uh simple thing it's it's something which could have been otherwise and is one particular way

00:06:05.040 and the particular way it is is uh that it says something true and useful about the world now

00:06:14.580 knowledge is in a sense an abstract thing because it it it's independent of its physical instantiation

00:06:21.720 i can speak words which uh which uh embody some knowledge i can write them down they can um

00:06:30.040 exist as uh movements of electrons in a computer and so on thousands of different ways uh so their

00:06:39.840 knowledge isn't dependent on any particular instantiation on the other hand it does have the

00:06:45.640 property that when it is instantiated it tends to remain so so the difference between let's say a piece of

00:06:55.260 of uh speculation by a scientist which he writes down and then that's that turns out to be a genuine

00:07:04.560 piece of knowledge that will be the piece of paper that he does not throw in the waste paper basket

00:07:10.120 and that's the piece that will be published and that's the piece which will be studied by other

00:07:16.480 scientists and so on so it is a piece of information that has the property of keeping itself physically

00:07:23.660 instantiated causing itself to be physically instantiated once it already is once you think

00:07:30.140 of knowledge that way you realize that for example the pattern of base pairs in in the dna of a gene

00:07:37.480 also constitute knowledge and uh that in turn connects with karl popper's concept of knowledge which is

00:07:47.020 knowledge that doesn't have to have a knowing subject it can exist in books abstractly or it

00:07:53.900 can exist in the mind or people can have knowledge that they don't even know they have right right

00:07:58.840 well i want to get to the reality of abstractions uh later on because i think that is very much at

00:08:04.620 the core of this but um a few more definitions what is the boundary between science and philosophy

00:08:10.620 or other expressions of rationality in your view because i think people are in my experience

00:08:15.200 profoundly confused by this and um many scientists are confused by this so i've i've argued for years

00:08:22.620 in several contexts about the unity of knowledge and i feel that you're a kindred spirit here so

00:08:27.680 how do you differentiate or fail to differentiate science and philosophy um well as you've just

00:08:34.200 indicated i think that science and philosophy are are both manifestations of reason and that the real

00:08:42.420 difference that that we should be uppermost in our minds between different kinds of ideas

00:08:47.360 and between different kinds of ways of dealing with ideas is the difference between reason and unreason

00:08:54.760 but uh among the the rational uh approaches to knowledge or different kinds of knowledge there is an

00:09:03.540 important difference between um science and other things like philosophy and mathematics not at a really

00:09:10.860 fundamental level but at a level which is of great practical importance often and that is that science

00:09:18.500 is is the kind of knowledge that can be tested by experiment or observation now i hasten to add that that

00:09:25.620 that does not mean that the content of a scientific theory consists entirely in its testable predictions

00:09:33.160 on the contrary a typical scientific theory its testable predictions are just a tiny tiny sliver

00:09:39.940 of what it tells us about the world now karl popper introduced his criterion of demarcation

00:09:47.100 between science and other things namely whether that science is the testable testable theories and

00:09:54.900 everything else is untestable and people have ever since he did that people have falsely interpreted

00:10:01.600 him as a kind of positivist he was really the opposite of a positivist and if you interpret him like

00:10:08.160 that then then his criterion of demarcation becomes a criterion of meaning that is he's interpreted as saying

00:10:15.720 that only scientific theories can have meaning right he's a verificationist uh yes and and yes so uh he's so

00:10:24.140 he's called a falsificationist right to to uh distinguish him from the other verifications but of course he

00:10:30.840 isn't uh it's it's a completely different conception and uh you know his philosophical theories themselves

00:10:38.960 are philosophical theories and yet he doesn't consider them meaningless quite the contrary right so um so

00:10:45.940 that's uh the difference between science and other things comes up when people pretend to have the

00:10:53.620 authority of science for things that aren't science but on the bigger picture the more important

00:11:01.120 demarcation is between the reason and unreason yeah i want to go over that terrain you just covered a

00:11:08.440 little bit more because you made some some points there that i i think are a little hard for

00:11:13.180 listeners who haven't thought about this a lot to parse and i think it's those are incredibly

00:11:18.380 important points so for instance this notion that that science reduces to what is testable

00:11:24.260 this belief is so widespread even among high-level scientists that that anything else anything which

00:11:32.320 you cannot measure immediately is somehow a vacuous claim in principle the only way to make a

00:11:39.280 credible claim or even a meaningful claim about reality is to essentially give a recipe for

00:11:46.140 observation that is immediately actionable it's an amazingly widespread belief so too is is a belief in

00:11:54.380 a bright line between science and every other discipline where we purport to describe reality and it's like

00:12:02.780 the architecture of a university has defined people's thinking so the fact that you you go to the

00:12:08.380 chemistry department to talk about chemistry and you go to the journalism department to talk about

00:12:14.860 current events and you go to the history department to talk about human events in the past these

00:12:21.100 separate buildings have balkanized the thinking of even very smart people into thinking that that all of

00:12:28.380 these language games are in some sense irreconcilable and that there is no common project i'll just bounce a few

00:12:34.880 examples off of you that some of our listeners will be familiar with but i think they make the point

00:12:39.200 so you take something like the assassination of mahatma gandhi right now that's a historical event

00:12:44.860 but anyone who would purport to doubt that it occurred if someone said well actually gandhi was not

00:12:50.900 assassinated he went on to live a long and happy life in in the punjab under an assumed name this is a claim

00:12:57.980 about terrestrial reality that is at odds with the data is at odds with the testimony of people who

00:13:04.120 who saw him assassinated it's at odds with the photographs we have of him lying in state and

00:13:09.860 there's there's an immense burden of reconciling this claim about history with the facts that we we

00:13:17.500 know to be true and the distinction is not between what someone in a white lab coat has said or facts that

00:13:25.460 have been brought into view in the context of a scientific laboratory with a national science

00:13:31.300 foundation grant it is the distinction between having good reasons for what you believe and having

00:13:35.840 bad ones and it's a distinction between reason and unreason as you put it so one could say that the

00:13:42.280 assassination of gandhi is a historical fact it's also a scientific fact it is just a fact even though

00:13:48.780 science doesn't usually deal in quantities like assassinations and you you're more a journalist or

00:13:55.980 historian to be talking about this thing being true you would be deeply unscientific at this point to doubt

00:14:01.880 that it occurred yes well i'd say that it's it's deeply irrational to claim that it didn't occur yes

00:14:08.740 and i i i wouldn't put it in terms of reasons for belief either i agree with you that that people have

00:14:17.200 very wrong ideas about what science is and what the boundary of scientific thinking is and what sort of

00:14:23.600 thinking can uh should be taken seriously and what shouldn't i think the it's it's slightly unfair to put

00:14:31.680 the blame on universities here uh i think the the this misconception arose originally for quite good

00:14:40.720 reasons it it it it's rooted in the empiricism of the 18th century and before and the the origin of science

00:14:49.520 which where it had to science had to rebel against the authority of tradition and of uh human authority

00:14:58.880 and say that uh try to give dignity and respect to forms of knowledge that involved observation and

00:15:07.440 experimental test right and so empiricism is the idea that knowledge comes to us through the senses now

00:15:14.880 that's completely false all knowledge is conjectural and comes from within at first and is intended to

00:15:22.640 solve problems not to summarize data but this idea that experience has authority and that only experience

00:15:32.640 has authority false though it is false though it is was a wonderful defense against previous forms of

00:15:39.600 authority which were which were not only invalid but stultifying right so it was a good defense but

00:15:48.240 not actually true and uh in the 20th century a horrible thing happened which is that people started taking

00:15:55.520 it seriously as not just as a defense but as being literally true and that almost killed certain

00:16:04.320 sciences and even within physics uh i think it it greatly impeded the progress in quantum theory so just to

00:16:14.560 come to a little quibble of my own uh i i think the the essence of uh what we want in science is good

00:16:23.440 explanation which and there's no such thing as a good reason for a belief a scientific theory is an

00:16:31.120 impersonal thing it it uh can be written in a book one can conduct science without ever believing the

00:16:39.040 theory just as a a good policeman or judge can implement the law without ever believing either of

00:16:47.600 the cases for the prosecution or defense just because they know that a particular system is better than

00:16:55.600 any individual human's opinion and the same is true of science science is a way of dealing with theories

00:17:03.760 regardless of whether one believes them and one judges them according to whether they are good

00:17:09.680 explanations and there need not be ever any any such process as accepting a theory because it is

00:17:18.640 conjectured initially and takes its chances and is criticized and as an explanation if by some chance

00:17:28.800 a particular explanation ends up being the only one that survives the intense criticism that science has

00:17:35.440 learned how to apply then it's not adopted at that point it's just not discarded right right i think

00:17:43.600 we may just have a we may be stumbling over a semantic difference in how we're using terms like reasons and

00:17:51.520 reasons for belief or a justification for a belief i i understand your quibble here that you're pushing

00:17:57.440 back against this notion that we need to find some ultimate foundation for our knowledge rather than this

00:18:04.080 this open-ended effort at explanation but let's table that for a second because obviously your

00:18:09.040 notion of explanation is is at the core here and i again i just want to sneak up on it because i don't

00:18:13.440 want to lose some of the the detail with respect to the ground we've already covered let's come back

00:18:19.120 to this notion of scientific authority because it seems to me there's a lot of confusion about this

00:18:24.240 about the nature of scientific authority it's often said in science that we don't rely on authority and

00:18:30.480 that's true and it's not true i mean when push comes to shove we don't rely on it and you make

00:18:36.560 this very clear in your book but we do rely on it in practice if only in the interest of efficiency so if

00:18:44.400 i ask you a question about physics i will tend to believe your answer because you're a physicist and i'm not

00:18:50.240 and if what you say contradicts something i've heard from another physicist well then if it matters to me i i will

00:18:55.920 look into it more deeply and and try to figure out the nature of the dispute but if there are any points

00:19:02.080 on which all physicists agree a non-physicist like myself will defer to the authority of that consensus

00:19:09.280 and this is again this is less a statement of epistemology than it is a statement about just the

00:19:14.560 specialization of knowledge and the unequal distribution of human talent and and just the

00:19:20.240 frankly the shortness of every human life and we simply don't have time to check everyone's work

00:19:26.240 and we have to rely on in some sense the faith that the the system of of scientific conversation

00:19:32.880 is correcting for errors and self-deception ah and fraud uh yes now okay i got myself out of the ditch

00:19:40.000 there yes yes exactly exactly that at the end what you said was right so you could call this authority

00:19:46.720 it doesn't matter really what what words we use but you know every every uh student who who wants to

00:19:54.480 make a contribution to a science uh is hoping to find something where every scientist in his field is

00:20:02.320 wrong absolutely uh so it's not impossible to take the view that you're right and every expert in the

00:20:09.680 field is wrong i think that what happens when we consult experts whether or not you use the word

00:20:16.080 authority it's not quite that that um we think that they're more competent it's i i think uh when you

00:20:24.160 refer to error correction that that hits the nail on the head i i think that there is um uh a process of

00:20:32.800 error correction in the scientific community that approximates to what i would use if i had the

00:20:40.800 time and the background uh to pursue it there and uh so if i go to a doctor to uh consult him about what

00:20:52.160 my treatment should be i assume that by and large the process that has led to his recommendation to me

00:21:02.800 is the same as the process that i would uh have have adopted if i had been present at all the stages

00:21:10.080 now it's not exactly the same and i might also take the view that there are widespread errors and

00:21:17.840 widespread irrationalities in the medical profession and if i think that then i will adopt a rather

00:21:26.000 different attitude i may choose much more carefully which doctor i consult and how my own opinion

00:21:34.640 uh should be judged against the doctor's opinion in a case where i think that the error correction

00:21:40.800 hasn't been up to the standard i would want and this is not so rare it's it's as i said every student is

00:21:49.760 hoping to find a case of this in their own field so every research student so when i travel on a plane i

00:21:58.640 expect that the maintenance will have been carried out to the standards that i would that i would use

00:22:04.480 well approximately to the standards that i would use well enough for me to uh consider that risk on

00:22:11.600 the same level as other risks that i take just by crossing the road it's not that i'm sure it's not that

00:22:18.160 yeah i take their word for it in any sense is that i have a positive theory of what has happened there

00:22:25.040 to get that information to the right place and that theory is is fragile it i i i can i can easily adopt

00:22:33.360 the a variant of it yeah well it's also it's probabilistic you're you realize that a lot of

00:22:40.400 these errors are washing out and that's a good thing but in any one case you you may judge the

00:22:45.680 probability of error to be high enough that you that you need to really pay attention to it and

00:22:51.600 often that as you say that happens in a doctor's office where you're not hoping to find it well

00:22:56.320 again let's i still picture us kind of circling your thesis and not yet landing on it science is

00:23:02.960 largely a story of our fighting our way past anthropocentrism this this notion that we are at

00:23:09.440 the center of things we are it has been yes we are not specially created we we share half our genes

00:23:15.840 with a banana and more and more than that with a banana slug so as you describe in your book this

00:23:21.040 is known as the principle of mediocrity and you summarize it with a quote from stephen hawking who

00:23:27.280 said quote we are just chemical scum on the surface of a typical planet that's in orbit around a typical

00:23:33.200 star on the outskirts of a typical galaxy now you take issue with this claim in a variety of ways but

00:23:40.320 but the result is that you come full circle in a way you you fight your way past anthropocentrism the

00:23:46.240 way every scientist does but you arrive at a place where people or rather persons i think that's the

00:23:52.480 formulation you tend to use and which you define in a special way suddenly become hugely significant

00:23:58.320 even cosmically so and so say a little more about that yes well so it's uh that that quote from

00:24:05.520 hawking is literally true but the philosophical implication he draws is completely false because

00:24:13.760 well one can approach this from two different directions first of all if you think of that

00:24:19.760 chemical scum namely us and possibly things like us on other planets and in other galaxies and so on if

00:24:28.320 they exist then um to study that scum is impossible unlike every other scum in the universe because

00:24:39.760 this scum is creating new knowledge and the growth of knowledge is profoundly unpredictable so as a

00:24:49.200 consequence of that to understand this scum never mind predict but to understand it to understand what's

00:24:57.280 happening here uh in entails understanding everything in the universe because uh as as i say in the

00:25:05.600 book i give an example in the book that um if the people at the seti project discover were to discover

00:25:12.800 extraterrestrial life somewhere far away in the galaxy they would open their bottle of champagne and

00:25:19.200 celebrate now if you try to explain scientifically what are the conditions under which that cork will

00:25:27.040 come out of that bottle then the usual scientific criteria that you use of pressure and temperature and

00:25:34.720 and uh biological degradation of the cork and so on will be irrelevant what is the most important factor

00:25:43.600 in the physical behavior of that bottle is whether there exists life on another planet and in the same way

00:25:51.600 anything in the universe can affect the gross behavior of things that affected by people and so in short to

00:26:01.600 understand humans you have to understand everything and uh humans or people in general are the only things

00:26:11.040 in the universe of which that is true so they are of universal significance in that sense then there's the other way

00:26:18.400 around it's also true that uh the the reach of human knowledge and human intentions

00:26:28.320 on the physical world is also unlimited so we are only used to having a relatively tiny effect on this

00:26:39.040 small insignificant planet etc and for the rest of the universe to be completely beyond our ken

00:26:44.160 uh but that's just a parochial misconception really just because we haven't set out across the universe yet

00:26:52.560 and uh we know that there are no limits on how much we can affect the universe if we choose to

00:27:01.360 so uh in both those senses we are by which i mean we and and the et's and the and the ais uh if they exist

00:27:12.080 there's no limit to to how important we are so we are completely central to any understanding of the universe

00:27:19.040 i'm struggling with the fact that i know how condensed some of your statements are and i i also know that

00:27:26.000 it's impossible for our listeners to appreciate just how much knowledge and conjecture is being

00:27:31.840 smuggled into each one so um i guess let's let's just deal with this this concept of explanation and

00:27:38.000 the work it does and um i mean first there's a few points you make about explanation that that i find

00:27:43.680 totally uncontroversial and even obvious but which are in fact highly controversial in in educated circles

00:27:49.520 and one is this notion that as you say explanation is really what lies at the at the bedrock of the

00:27:56.560 scientific enterprise and the enterprise of reason generally explanations in one field of knowledge

00:28:02.320 potentially touch explanations in many other fields and even all other fields and this suggests a kind

00:28:08.000 of a kind of unity of knowledge but you make two claims and really especially bold claims about

00:28:14.640 explanation which i do see some reason to doubt and as i said i'd rather not doubt them because

00:28:20.400 they're incredibly hopeful claims so i guess the first to deal with is is the power of explanation

00:28:25.600 i guess i'll divide these into there's the power of explanation and there's the reach of explanation

00:28:30.800 and these may not be entirely separate in your mind but let's just deal with it there's a separate

00:28:35.360 emphasis here you make what what is a seemingly extraordinary claim about explanation which at first seems quite

00:28:42.080 pedestrian you say that there's a deep connection between explaining the world and controlling it

00:28:48.000 everyone understands this to some degree i mean we all see that the evidence of it all around us in

00:28:53.200 our technology and people have this phrase knowledge is power in their heads so there's nothing so surprising

00:29:00.080 about that but you do go on to suggest and you did just suggest it in passing that knowledge confers

00:29:06.240 power without limit or or it is limited only by the laws of nature so you actually say that anything

00:29:12.880 that isn't precluded by the laws of nature is achievable given the right knowledge because if

00:29:18.640 something were not achievable given complete knowledge then then that itself would be a regularity

00:29:24.400 in nature that could be explained in terms of the laws of nature so there are really only two possibilities

00:29:29.360 either something is precluded by the laws of nature or it is achievable with knowledge is that do i have you

00:29:34.160 right there yes and that is uh that's what i call the momentous dichotomy uh that there can't be any

00:29:40.480 third possibility other than those two and i i think you've you've given not only a statement of it

00:29:46.000 but you've given a very short proof of it right there so so how isn't this just a clever tautology

00:29:53.440 analogous to the ontological argument proving the existence of god so many of our listeners will know

00:29:58.320 that according to saint anselm and and descartes and many others it's believed that you can prove the

00:30:04.480 existence of god simply by forcing your thoughts about him to essentially bite their own tails and

00:30:10.640 for instance i could make the following claim i can form a clear and distinct concept of the most

00:30:16.480 perfect possible being and such a being must exist therefore because a being that exists is more perfect

00:30:24.720 than one that doesn't and i've already said i'm thinking about the most perfect possible being

00:30:28.800 so and existence is somehow a predicate of perfection now of course most people will

00:30:34.400 recognize certainly most people in my audience will recognize that this is just a trick of language

00:30:38.880 you know it could be used to prove the existence of anything i could say i'm thinking of the most

00:30:42.960 perfect chocolate mousse and it must exist therefore because a mousse that exists is more perfect

00:30:48.080 than one that doesn't and i already told you that i'm thinking of the most perfect possible mousse

00:30:51.920 what you're saying here doesn't have the same structure but i do worry that that you're

00:30:56.000 performing a bit of a conjuring trick here because and i'll just ask the question for instance why

00:31:02.080 mightn't certain transformations of the material world be unachievable even in the presence of

00:31:08.640 complete knowledge merely by and this is something i realize you do anticipate in your book but i want

00:31:15.200 you to flesh it out for the listeners merely by let's say a contingency of geography you know so that

00:31:21.120 for instance you and i are on an island and and one of our friends comes down with an appendicitis

00:31:26.320 and let's say you and i both we're both competent surgeons we know everything there is to know about

00:31:31.280 removing a man's appendix but it just so happens we don't have any of the necessary tools and everything

00:31:37.040 on that particular island is just has the consistency of soft cheese right so there's this just by sheer

00:31:42.720 accident of our personal histories there is a gap between what is knowable and what is in fact known

00:31:49.120 and what is achievable even though there are no laws of nature that preclude our performing an

00:31:53.520 appendectomy on on a person why mightn't every space we occupy in some just by a contingent fact of

00:32:01.200 our of the way the universe is not introduce some gap of that kind uh well there are there are definitely

00:32:10.720 gaps of that kind and they are all laws of nature for example uh you know that i am an advocate of

00:32:18.080 the many universes uh interpretation of quantum theory or the many universes version of quantum

00:32:23.920 theory and that says that there are other universes which the laws of physics prevent us from getting to

00:32:30.560 um there is also uh the the fineness of the speed of light which doesn't prevent us from actually

00:32:36.240 getting anywhere but it it does prevent us from getting anywhere in a given time so if we want to

00:32:41.600 get to um the nearest star within a year uh we can't do so because of the accident of where we happen to be

00:32:49.680 if we happen to be nearer to it we could easily get there in a year and in your example if there's no

00:32:56.240 metal on the on the island then it may be i mean it's rather a complicated thing to calculate but there

00:33:03.200 will be a fact of the matter of whether and it could easily be that no knowledge present on that

00:33:10.800 island could save the person because no knowledge could transform the resources on that island into

00:33:18.880 the relevant uh medical instruments so that's going to that that's a um a thing that a restriction that

00:33:27.600 the laws of physics apply because we are in particular times and places and and and of course the most

00:33:36.400 powerful thing is we don't in fact have the knowledge to do most of the things that we would ideally like

00:33:43.040 to do so that's another uh restriction but that that's completely different from the from i think what

00:33:51.200 you're imagining which is that uh there is some there might be some reason why we for example why we can

00:33:58.080 never get out of the solar system getting out of the solar system is uh if that were impossible it would

00:34:05.200 mean that there is some for example some number some constant of nature 1000 astronomical units or something

00:34:13.680 uh which limits the other laws of nature that we already know now there might be other laws of nature

00:34:21.120 uh you know when you say how do we know that there isn't that that's that's a little bit like

00:34:28.240 like uh and if i can turn your objection around the other way you know that's a little bit like uh creationists

00:34:35.120 saying how do we know that the earth didn't start 6000 years ago there is no conceivable evidence

00:34:43.040 that could prove that didn't or that could distinguish the 6000 year theory from a 7000 year theory

00:34:50.640 and so on that there's there's no way that evidence can be brought to bear on that and that that leads us

00:34:56.800 to explanation again which is another difference between my um argument which i i think is valid and the

00:35:06.800 the uh ontological argument the existence of god that is a as you said it's a perversion of logic the

00:35:14.880 argument purports to use logic but then but then smuggles in assumptions like that the that

00:35:22.880 perfection entails existence for example right to name a simple one whereas my uh proof as it were

00:35:30.320 is an explanatory one it it isn't just this must exist it's that if this doesn't exist something bad

00:35:38.000 would happen for example the universe would be controlled by the supernatural or the laws of

00:35:45.600 nature would not be explanatory or something of that kind which which i think is just leading to

00:35:51.920 the supernatural in a different way so um wrote i i think this this the argument works because it's

00:35:58.880 explanatory there isn't a whole of the same i mean you can't prove that it's true of course but

00:36:04.720 but there isn't a hole in it of the same kind as in the ontological argument the the fishiness i was

00:36:12.080 detecting worries me less than what i'm going to go on to talk about it regarding the reach you

00:36:18.160 posit for explanation but it's more a matter of emphasis is if you're saying that we could have

00:36:23.440 a complete understanding of the laws of nature and yet there could be many contingent facts about

00:36:30.560 where we are let's say a distance our current distance from a star we want to get to which would

00:36:35.360 preclude our doing anything especially powerful with this knowledge and you're going to shuttle

00:36:40.880 those contingent facts back into this claim about well this is just more of the laws of nature i mean

00:36:45.840 this is these these facts about us are regularities in the universe which are themselves explained

00:36:51.360 by the laws of nature and therefore we're back to this dichotomy there's just the laws of nature

00:36:56.000 and there's the fact that knowledge can do anything compatible with those laws i guess the concern

00:37:02.240 is in various the thought experiments in your book you make amazingly powerful claims about the utility

00:37:10.000 of knowledge so for instance at one point you talk about a region of space you know a cube the size

00:37:15.120 of of the solar system on all sides that's more representative of the universe as it actually is which

00:37:21.600 is to say it's nearly a vacuum it's just we're talking about you know a cube of intergalactic empty

00:37:26.560 space that has more or less nothing but stray hydrogen atoms in it and you talk about the process by which

00:37:34.000 that could be primed and become the basis of a of the most advanced civilization that we could imagine you

00:37:42.160 might maybe spend a minute or two just talking about how you get from virtually nothing to something

00:37:46.800 there but it is a picture of almost limitless fungibility of the universe on the basis of

00:37:55.600 knowledge and that's a um take us to deep space for a moment yes so you and i are made of atoms

00:38:02.480 and that already gives us a tremendous fungibility because we we know that that atoms are universal

00:38:09.600 the properties of atoms are the same in this cube of space millions of light years away as they are

00:38:16.560 here so we're talking mostly when we're talking about about the power of knowledge to uh achieve

00:38:24.560 things to control the world we're not talking about tasks like uh saving someone's life with with just

00:38:32.720 the resources on an island or getting to a distant planet in a certain time we're talking about the

00:38:39.280 generic thing that we're talking about is converting some matter into some other matter

00:38:45.600 so uh what do you need to do that well generically speaking what you need is knowledge what would

00:38:52.320 have to happen is that this cube of almost empty space will never turn into anything other than boring

00:39:00.240 hydrogen atoms unless some knowledge somehow gets there now whether knowledge gets there or not

00:39:09.600 depends on decisions that people with knowledge uh will make at some point i think i think there is no doubt

00:39:17.360 that knowledge could get there if people with knowledge decided to do that for some reason

00:39:23.680 uh i can't actually think of a reason uh i can't actually think of a reason but if they did want to do

00:39:28.480 that it's not a matter of futuristic speculation to know that that would be possible that then it's a matter

00:39:34.800 of transfer transforming atoms in one configuration to atoms in another configuration and we're now getting used to

00:39:44.000 the idea that that is an everyday thing we we now have 3d printers that can convert just generic stuff

00:39:53.600 into any object provided that the knowledge of what shape that object should be is somehow encoded into the

00:40:01.680 3d printer and a 3d printer with the resolution of one atom would be able to print a human if it was given the

00:40:08.400 right program so we already know that and it's although it's in some sense way beyond present

00:40:15.200 technology it's not way beyond our present understanding of physics it's well within our

00:40:21.680 present understanding of physics it would be an absolute absolutely amazing turn up for the books

00:40:28.560 if that turned out to be beyond physics something i mean beyond what we know of physics today

00:40:33.840 uh the the idea that new laws of physics would be required to make a printer uh is is just beyond belief

00:40:40.880 really to just take us from the beginning in an empty space you have to you start with hydrogen and

00:40:44.800 you have to get heavier elements in order to get to your printer yes so you have to it has to be primed

00:40:51.360 not just with abstract knowledge but with knowledge instantiated in something we don't know what the

00:40:56.480 smallest possible universal constructor is that is a just a generalization of a 3d printer something that

00:41:03.520 can be programmed either to make anything or to make the machine that would make the machine that

00:41:09.280 would make the machine to make anything etc so one of those with the right program sent to empty space

00:41:17.040 would first convert well would first gather the hydrogen presumably by some kind of electromagnetic

00:41:23.840 broom sweeping it up and compressing it then converting it by transmutation into other elements

00:41:32.960 and then by chemistry into what we would think of as raw materials and then uh using space construction

00:41:42.560 which is the kind of thing that we're almost on the verge of being able to do uh into a space station

00:41:49.600 and then the space station to instantiate further people to generate the knowledge to suck in more

00:41:56.720 hydrogen and make a colony and well they're not going to look back from there how do you want me to

00:42:03.440 describe it right it's just a very interesting way of looking at um knowledge and its place in the

00:42:08.640 universe i think before i get onto the the issue of the reach of explanation and my quibble there i i just

00:42:14.640 want you to talk a little bit about this notion of spaceship earth which i i loved how you debunk this idea

00:42:20.480 there's this idea that the biosphere is in some way wonderfully hospitable for us and that if we built

00:42:27.360 a colony on mars or some other place in the solar system we'd be in a fundamentally different

00:42:32.400 circumstance and a perpetually hostile one and that is a an impressive misconception of our actual

00:42:39.360 situation and you have a great quote where you say that the the earth no more provides us with a life support system

00:42:45.440 than it supplies us with radio telescopes so say a little more about that yes so we we evolved

00:42:52.320 somewhere in east africa in the great rift valley and that was a an environment that was particularly

00:43:01.200 suited to having us evolve and life there was sheer hell for humans nasty brutish and short is it doesn't

00:43:10.720 begin to describe how horrible it was but we transformed it we or rather not actually our

00:43:16.720 species but the species that are some of our predecessor species already um changed their

00:43:23.200 environment by inventing things like clothes fire and weapons and thereby made their lives much better still

00:43:31.680 horrible by our present-day standards and then they moved into environments such as as i also say in the

00:43:39.600 books such as oxford where i am now and it's december and if i were here at this very location

00:43:47.440 with no technology i would die in a matter of hours and nothing i could do could prevent that so you are

00:43:56.240 already an astronaut very much so your condition is as precarious as the condition of those in a well

00:44:04.240 established colony on mars that can take certain technological advances for granted and there's no

00:44:11.840 reason to think that future doesn't await us barring some catastrophe placed in our way whether of our

00:44:17.520 own making or not yes uh and also that there's another misconception there which is related to that

00:44:26.160 misconception of the earth being hospitable which is the misconception that applying knowledge is effort

00:44:35.440 it's creating knowledge that is effort applying knowledge is uh what we call automatism it's it's

00:44:43.040 automatic as soon as somebody invented the idea of for example wearing clothes from then on the clothes

00:44:52.320 automatically warmed them so long as they were wearing the clothes it didn't require any more effort

00:44:57.920 of course the clothes with there would have been things wrong with the original clothes such as that

00:45:02.320 they rotted or something and then people invented ways of making better clothes but at any particular

00:45:07.920 stage of knowledge having got the knowledge the rest is automatic and now we have invented things like

00:45:14.080 mass production unmanned factories and so on we take for granted that that uh that the water gets to us from the water supply

00:45:25.360 without anyone having to carry it laboriously on their head in pots it doesn't require effort it just requires

00:45:33.520 the knowledge of how to install the automatic system much of our life support is automatic and every time we

00:45:41.920 invent a better way of life support we then make it automatic so the the people on the moon living on the

00:45:50.080 moon in a lunar colony to them keeping the vacuum away will not be a thing they think about they'll

00:45:58.320 take that for granted what they will be thinking about is new things and the same on mars and the same in deep

00:46:04.080 space right well yeah and again that's an incredibly hopeful vision of our possible future um and so

00:46:11.520 thus far we've covered territory where i really don't have any significant doubts despite the fact

00:46:16.480 that i pretended to have one with the ontological argument so let's get to this this notion of the

00:46:21.280 the reach of explanation because you seem to believe that the reach of our explanations is unbounded

00:46:28.160 which is to say that anything that can be explained either in practice or in principle can be explained by

00:46:34.880 us uh which is to say human beings as we currently are so you so you seem to be saying that that that

00:46:40.640 we alone among all the earth's species have achieved a kind of cognitive escape velocity and we're capable

00:46:48.000 of understanding everything and you you contrast this view with um what you call parochialism uh which is

00:46:54.640 a view that i have often expressed and you know many scientists have expressed as a max tegmark was on my

00:47:00.080 podcast a few podcasts back and and we more or less agreed about this thesis and so the thesis of

00:47:06.640 parochialism is just evolution hasn't designed us to fully understand the nature of reality we're we're

00:47:12.480 not you know either the very small the very large the very fast the very old these are these are not

00:47:18.000 domains in which our our intuitions about what is real or what is logically consistent have been

00:47:23.280 tuned up in any in any way by evolution and insofar as we've made progress here it has been by a kind

00:47:31.200 of happy accident and it's an accident which gives us no reason to believe that we can by dint of this

00:47:37.200 accident travel as far as we might like across the horizon of what is knowable so which is to say that

00:47:43.440 if a super intelligent alien came to earth for the purpose of explaining all that is knowable to us

00:47:50.480 he or she may make no more headway with us than you would if you were attempting to teach the

00:47:55.840 principles of quantum computation to a chicken and so i want you to talk about why that analogy doesn't

00:48:02.560 run through why why parochialism this notion that we are we just we occupy this a kind of cognitive

00:48:08.720 niche that there is really no good evolutionary reason to expect we can fully escape why that why

00:48:15.280 that doesn't hold true yes well you've actually made two or three different arguments there all

00:48:22.160 of which are wrong so if you'd like to continue listening to this conversation you'll need to

00:48:29.440 subscribe at sam harris.org once you do you'll get access to all full-length episodes of the making

00:48:34.640 sense podcast along with other subscriber only content including bonus episodes and amas and the

00:48:41.040 conversations i've been having on the waking up app the making sense podcast is ad-free

00:48:45.920 and relies entirely on listener support and you can subscribe now at sam harris.org

Making Sense - Sam Harris - December 16, 2015

#22 — Surviving the Cosmos

Episode Stats

Length

Words per Minute

Word Count

Sentence Count

Misogynist Sentences

Hate Speech Sentences

Summary

Transcript