data gives children an edge when they get to kindergarten. thank you and it was a great last question. [applause] and the informed tradition all speakers are asked, mary anne what is your 62nd idea to change the world? >> i think what would really change the world is if people came to see that their individual person out experiences are reflections of a much larger force. i think most of the time especially in the united states

when people experience inequality, they experience it as like a personal problem that they individually need to fix rather than a social problem that needs to be solved together. so if we could achieve this fundamental shift and outlook so that people didn't think where they ended up with solely just from their own actions but actually were so heavily influenced by all the social forces that are around them that would change the world. that would lead people to demand policies that provide security for families and if we did that i think we would all worry less than three more. [applause] >> and with that and a huge, huge applause and

congratulations for such work to mary anne this meeting of the commonwealth club and forum is adjourned. thank you. >> host: hello dr. caleb

scharf it's wonderful here to have you. i found your book fascinating and a terrific read and i'm thrilled to be here. the great thing is i get to about -- get to ask you about some big questions that most people would not dare to answer and that's the real fundamental thought. so your book is called "the copernicus complex." maybe you could tell us a little bit about what that is. >> guest: absolutely. the copernicus complex is really a phrase that's trying to capture one of the aspects of what i think is perhaps the biggest questions can ask and sometimes we ask it

nonscientific way. the book is really about the scientific question of whether or not we are alone in the universe. the copernicus complex refers to way we feel about ourselves. on the one hand, from copernicus we wrote that we are not central, we are not special in any way and that idea has propagated through the centuries and is really driven a lot of modern science. it is really the core of modern science and idea that has become known as cosmic mediocrity. it's nothing special or interesting about it. >> host: this is a complex we carry around. >> guest: the complex is that instinct tends to make us feel special to all of us as humans

unless we are extremely downbeat and tend to wake up in the morning and think that the world revolves around us but rationally we know it doesn't. copernicus gave us that idea and so we really have this little battle going on in our heads i think and i think scientists have the sense science has it as well that on the one hand rationally we can see that it may not be special or central to the universe. >> host: we as humans? >> guest: certainly as individuals and the species and extended to the rest of life on earth. think about it and say look perhaps this happens somewhere else. but at the same time we like to think it's special. that's just built into it so the complex is dealing with all of this is really part of it. that's part of the theme of the book except exploring it in a

more sophisticated analytical way. what does it really mean this copernicus complex and how might it hinder or help us decides? >> host: the premise of the book is sort of we are special or we are not special or some happy medium in between or are we are both sorted unique and we are also changing? >> guest: that is actually really the conclusion i get to in the book. when i set out to write the book there were a couple of things that molded -- motivated me. part of it was telling the story above incredible signs that this happened in really the last couple of decades that is moving us toward a point where we might be able to answer in real numbers this question of whether or not there's anything out there at all like this and other

life in the universe. but at the same time we are coming up with contradictory evidence. we have evidence that really stands out of the copernicus worldview which is mediocrity. we can't know if there are billions of other planets in our galaxy. on the face of it that is a beautiful thing. >> host: in this started with the copernicus' binding that we are not the center of the solar system. >> guest: i think you can trace it back to that and of course copernicus was actually the first person to say that the earth might not be the center of everything. it might take us back to the ancient greeks, aristotle thought that the earth was at the center of things and other greek philosophers like that idea. it wasn't logical how that could possibly be so it took a long time for copernicus to come

along. copernicus was reading what scientists were doing in the middle east at the time and he too understood some of the history of ancient greek science. it didn't come to him in a flash i think an assembled information that was already out there. so this idea on the one hand the supports that copernican worldview. we are absolutely not central. einstein tells us that in an expanding universe there is no center to that expansion. it's kind of the ultimate extension of the copernican principle but we also have found evidence that there will be billions of planets in our galaxy beyond those in the solar system. we have learned that the carbon chemistry, the building blocks are everywhere.

carbon-based molecules throughout space. >> host: the chemical potential for life is everywhere our chemical atmosphere is special or unique. >> guest: it seems that way so there is a host of evidence that supports this notion of positive mediocrity but there's also a host of evidence that might suggest it's not so simple. this is really a big piece of the book is stressing these two sides to of the equation. the other side to the equation is that yes we found new planets and stars, thousands at this point and from that we can extrapolate that there are billions but the configuration of our solar system and the arrangements of the planets and types of planets and even the types of stars in the orbit mean

that we are slightly unusual case. the solar system is not the most frequently occurring type of place. >> host: what makes it unusual or special? >> guest: there's a fingerprint in terms of the orbits and the planets related to the planets themselves. planets the planets are relatively a circular path. there was a path that newton was able to compute in that we can observe in detail in their relatively spread out. we also have a range of planetary types called small rocky planets like the earth or gas giant planets like jupiter and places like neptune and what we have learned is that the majority of planetary systems are configured somewhat differently. orbits tend to be less circulate more elliptical for example.

the orbit is quite spread out as if planet formation run a muck and the system made lots of planets and they are clustered around the parent star like bugs around a pot of honey or something. there are also types of planets that simply don't exist in our solar system. for example there are planets out there which are very abundant. 60% of the solar system include planets called super earth. they are somewhat larger than the earth but not as large as the planet like jupiter. they might have expected there could be such things but we didn't know for sure and we didn't know that most other systems contain one of those worlds. and what does that all mean for life? that's a big question. we don't know the answer to that. >> host: shows a little bit that we are unique and we may be

in a special circumstance. >> guest: is one's piece of evidence that suggests that you know there is something not quite as mediocre as we thought about our solar system. connecting that to the presence of life is a very difficult ta task. the origins of life and really what is necessary to put it all in place but we can also look at the history of life on earth and try to use that as some sort of am example or template so again on the side of something special going on we look at the history of life on earth, you can see that there are a number of things that have to line up in order for complex life, not necessarily us that we could be talking about bunny rabbits or sheep, complex history of life. for that to exist a number of things have to be necessary to do certain type of environment and climate behavior and certain events in deep history of

biology where new types of cells tend to be complex cells for example. >> host: have these i have these things than spelled-out? is there a list, an ingredient list like check, check and you get all these names and then i can occur? if you take one out, is this something that is roughly established or conjectured? >> guest: i would say not really. this is shooting in the dark a little bit. if we had that magic formula you need this, you need this, you need this you would get life and we could answer a lot more abo about. existing life elsewhere and even in our own history. in the book i argue that making these types of statements are extremely dangerous. in the book i really go into the detail.

life is dangerous and planets are dangerous. in the universe is a dangerous place. you have to go with the flow. part of the difficulty is that these are all things that take on meaning after the event. so part of the argument i make in the book is we could be sitting on another planet in different history and i could have tentacles and i'd be waving them around in my purple scaled skin and having the same interview somewhere and saying yes you know if we hadn't had six months around our planet we wouldn't be here today. so there's a danger in this interpretation of things after-the-fact. one of the arguments i make in the book is these things are very intriguing. it is intriguing that apparently our existence of complex life is contingent on a number of their

improbable things happening across the last 4 billion years. if you add it all up it's extremely unlikely but it's only after-the-fact that you make that inference. my argument in the book are one of the arguments is we don't actually learn much from us at all. >> host: you make the analogy of a baseball flying up into the stadium and you being, happen to be the one to catch it. >> guest: that's right. >> host: that seeming improbable but if you are to sort of wind the clock back that could have landed in someone else's hands and you know was going to land somewhere. >> guest: exactly. if you are sitting there i think any of us would say that's incredible and you start looking back at the events that led to that. if i hadn't picked up his seat

in the stadium and if i hadn't shown up at this time were decided to come to the game today this wouldn't have happened. all seems very unlikely but if you look around you in d.c. 50,000-dollar people in the stadium he began to realize it's going to land in someone's hand. someone hits a good ball and applies into the crowd someone is going to catch it. that person would have had the same conversation. >> host: and if we had millions of planets? >> guest: now the difference between the baseball stadium in our situation in terms of the universe is it's as if you were sitting in the baseball stadium and he don't know anyone else is sitting there. if you don't know you have to ask am i the only one that caught the ball and he can't really answer that question. if that were the case he would be incredibly unlikely. i think a similar situation exists with any interpretation of the history of life on earth

and trying to extrapolate that to say things about whether or not we are very unusual. there's no other life in the universe is essentially or otherwise. so one of the themes in the book is taking that kind of argument which has its flaws as i describe what the baseball analogy, but at the same time you can't totally dismissive. it could be correct but it could be wrong. we don't know and these other factors like the fact that our solar system seems to be somewhat unusual. for example we don't orbit the most common type of star but is that relevant for the existence of life? we don't really know but it raises a flag. >> host: one of a very interesting aspects of the book which is not necessarily obvious

is that you spend a lot of time talking about microbes. in fact he began the book with the dutch scientist who discovered for the first time that there are actually little creatures that are in our saliva and you begin the book with this. so microbes play a very important role in this story. could you talk a little bit about that? >> guest: sure. as you say i begin the book in this moment where perhaps the first time ever a human sees into a drop of water and realizes the organisms are so small that they can't see them with your human eye greedy can even see them with a magnifying glass. there are powerful optical instrument to appear even into

the cosmos really looking into buying the cosmos in a drop of water. you have to ask yourself are we in that situation except we aren't a glass of water. one of the things that made me want to write the book was realizing that some of these clues, some of these ideas about the nature of life are not just coming from astronomers and scientists and understanding planets in the abundance of the world but is coming from biology. there are philosophical arguments about what life is and mechanical arguments about something that replicates and changes and so on but there's

also a similar question which is if you take life on earth, give me a laundry list of what is a consist of? most of it in terms of number, biomass genetic diversity and single celled microorganisms significant complex life, humans and our status in a planetary system, planetary environment. we talk about humans. >> host: you could consider it threatening if you think about it. the fact that microbial cells are less than, maybe not pound for pound but if you're counting cells make up less than human cells. >> guest: that's right. we carry around more single

celled celled microbes than our own cell numbers which is an extraordinary thing. obviously the field of microbiology revolutionized by getting to understand how these microbes are not just necessary for function as large multicellular organisms but they also play a role in making us who we are. individuals and cultural groups, you name it. so what i wanted to show in the book was i would take that idea to human microbes which is in hot pocket -- hot topic and try to connect into the broader context which is the context of all of life on earth dominated by microbes and these microbes that long before we came along and long before multicellular life came along maybe one or 2 billion years ago even before oxygen breathing life came

along, essentially the same types of single celled organisms planet for their own benefit not some conscious intent, but they have been interacting with the planetary environment for the last 4 billion years give or take. we don't know exactly when life began although it looks like it began pretty early. it was formed some 4.5 billion years ago and certainly around 4 billion years there's evidence of living organisms on the planet. so to make the connection that in a sense we also are being engineered by the organism, the same organisms that have been engineering everything else on the planet chemically, the makeup of the continental masses of the earth and the chemistry of the ocean are interlinked with life. >> host: one of the other

interesting things they point out is that microbes and bacteria, algae form sorted a backup for our dna. that was a very interesting insight. >> guest: this is something i hadn't fully appreciated until a few years ago that if you look at life and not just in us but spread over every rock and crevice on the planet there's a far number of metabolic processes and how you extract energy and raw materials. we breathed oxygen for example and oxygen make metabolism and respiration. organisms make use of methane. they generate methane or use methane. these organisms using ion and manganese compounds, that's how they survive.

but finite number of these metabolic tools of life on earth has converged on 10 of them. the interesting thing is the genetic information that describe machinery for which you make use of any metabolic process is highly conserved. in other words it's everywhere. organisms obviously passed down from generation to generation but microbes might might koberger -- microbial carry around the data that isn't necessarily his. it looks like a giant distributed system the ultimate system where if you take a picture on your cell phone in immediately uploaded to several places and you flush your cell phone down the toilet it doesn't matter. the cat pictures are distorted

in fact it's stored in multiple copies. it looks like microbial -- does that and it's been doing that for millions of years. the realization being that you could come along and destroyed 99.9% of life on the planet tomorrow, if you could do that. the odds are extremely high the microwill contain this pre-genetic code from metaboli metabolism. in other words what life is learned over the 4 billion yea years, this is one mechanism by which life on earth for 4 billion years because once it's found the two solutions to how you survived, holds onto

them tight, holds onto them tied in a very robust way, informational way. and that has the hallmarks of something that could be more general. his universal rule, how life entered more than a thousand years and is back on the mechanism which we really didn't understand until recently. we have more of a picture of well if you kill off all the dinosaurs, that's it, they are gone but actually microbes in dinosaurs whatever they figured out, some of them are probably still around. all of the genetic material is still around pass from microto microbes and spread across. was that is one way that life has managed to survive for 4 billion years through ice ages and all the events that could have wiped out life. >> guest: that's right, yeah.

it's a number things. one suggests that life is far more tenacious than imagined a few years ago. certain organisms are extremely good at surviving difficult environments for us. environments with heat or pressure but beyond that life, once it really is on the planet can preserve much more complex information and detailed information long-term. i think that makes it tempting to say well this is such an obvious engineering system that if there's life anywhere else it may employ the same kind of mechanism to say look perhaps i can get extra clues for how to look for that life. >> host: if we are looking for

life on other planets, which i guess we are and have been for a very long time, what exactly are we looking for? >> guest: well it's a good question and i think you could have asked that question back in the 1950s at the dawn of the space age they might say we might find vegetation on mars or something like that. people really did feel that way and it wasn't until. >> host: trees and stuff. >> guest: absolutely. it's perfectly fair because they had not seen a place like mars up close enough to realize that was impossible. in fact if you look back at when the first flyby of mars occurred in the early space age and images close-up from mars came back enormously disappointing. we hadn't realized that it was a desert like and desolate. so what has happened is the emphasis now has shifted less

than looking for trees are sheep wandering around or anything really obvious that looking for the chemicals that indicate life. life is a messy phenomenon. it rearranges things around itself. chemicals that takes them in chemicals that alters, it chemical balance in the environment among other things but one of the key approaches these days is to look for chemicals and this is what is happening on mars for example. in recent years there has been discussion. >> host: water? >> guest: water is considered part of a environment that might harbor biochemistry that we are familiar with. liquid water. liquid water is particular important thing because it's a remarkable biological solvent

and it's deeply involved in integrated with our biochemistry and when i say our biochemistry, the biochemistry of all living things. the water being the mantra for places like nasa because that's a necessary but not sufficient life. but what we would really like to look for are signs of some strange chemical and balance that is naturally explained by the existence of life. for example somebody who has claimed they have seen atmospheric methane on mars and methane on mars shouldn't stick around for very long. if you see at something put it there reasonably. it could reasonably be a geophysical phenomenon. it could also be that maybe there are methane producing bacteria somewhere on mars.

we don't know yet and the evidence right now is suggesting that perhaps there is methane after all but it's the kind of thing that gets me very excited. something is strange. life is a dynamic offering of the border between order and disorder. >> host: so we are looking at chemical finds that her on the border? >> guest: exactly. and that's something that's also being applied to the study of exoplanets. that's really a big focus and planets the size of the earth and a signal that you can achieve with modern telescopes looking at the chemical balance of a very weak star. the hope is in a few years time there will be instruments that

will have sensitivity that can sift through the atmosphere of a earthlike planet and look for signs of chemicals. oxygen and things like that. >> host: we are going to take a quick break and we will be back. >> host: in the book you talk about the potential of actually measuring the probability that life exists elsewhere and i thought that was a fascinating idea. most of us think of just looking forward in seeing if we can find it.

could you tell us a little bit about how we might possibly measure it? >> guest: yeah, so it's a very ambitious concept. to look beyond where we are now and say well let's suppose that we really can begin to detect the signs of life and what's the next step and i think the ultimate step is to establish how frequently life occurs in the universe. how do we do that? well it may be very very difficult. i talk about this to some extent in the book. taking these chemical measurements of the composition of the planetary atmosphere and learning how to pin down the chemical signature that really gives you evidence that there's life on the planet or other characteristics of planets and the colors that you see on the surface of the planet that is

related to whether or not something that might be life for as we understand that it could be something different. there are number of techniques and this would give you really a probabilistic measurement of whether there's life on a planet and how much life there might be. >> host: so you take an individual planet and assign values to these various characteristics? >> guest: yes, to build a rather unconventional fingerprint for a planet and when i say unconventional kinds of things that perhaps we think of for a planet. there are a number of factors to do with chemicals and to do with the variations during a given annual cycle so things that we measure for years but we don't actually look at them in that respect. we know there's life and

bringing together in formulating a fingerprint. a great system if you will. this is a grade eight life bearing planet for example. so one of the interesting things about looking for life is the focus has naturally been on just finding out whether or not there's anything else out there. that's completely reasonable. but what's the next step? what's the ultimate place you can go to with that? the reason i discussed this in the book is that it's closely related to something even deeper and that is the question of why and how exactly this universe resembles life. clearly her universe is suitable to life in at least one place, here but how suitable is that overall? a universe that we can observe which a universe in which life has traveled to for 4.5 million

years. usually just called the observable universe, it's finite. it contains a few hundred billion galaxies and a couple hundred billion stars. there are a finite number of places where life might occur and it means the observable universe can take finite grounds of life. it might just be one instance but chances are it's probably something between one and a larger number. but why that number? is one living planet for 20 solar systems. why is it that number? one of the arguments i try and make in the book is determining that could be extremely important not just in evaluating some statistical numerical way to true significance, putting a number to it but also as perhaps

a code of deeper physics. this really loops back to ideas that have been discussed in the past. for example there's an anthropic principle. so this really came up in the middle of the 20th century. since we started trying to understand the nature of the universe. it wasn't quite clear at that time whether the universe was finite and age or whether it's always been here. the steady-state universe which is the same in time and space everywhere. and the big bang. we now think possibly there was a big bang. there was a starting point for the universe. but a lot of people began to see that well there are certain properties and absolute strength of gravity for example and eight

absolute strength of electromagnetic forces. these fundamental properties and constants of nature that if you altered any of them a little bit it would be very different. then we began to ask and the baseball problem again. how likely is it for universe to end up with all the right features that would lead to organisms like the earth and they can seem somewhat in likely so this was intimately related with the beginnings of what we now call the idea of multi-verse. the idea that there might be not just one universe like this but numerous numbers of other universes. there's no evidence for this now. it fits with the number of ideas in cosmology. the interesting thing about it is that it deals with the

nagging question up why is there only one universe and there is only ever been one universe. why was it suitable for life to emerge to make that alteration and equally you can use the fact of our existence to perhaps understand something about the deeper solar system. some might say we are made of carbon molecules. carbon comes from stars. stars that use the elements to make things like carbon but if you tweak the physics of the universe a little bit. he wouldn't do that. he wouldn't make carbon. or you might not make enough carbon to ensure that they would be a planet somewhere with lots of carbon compounds out of which life might -- a vicious anthropic principle which is a bit of bad choice it could be

any life. the very existence of life and telling you something about the deeper physics of the universe. >> host: interesting so we have sort of a closed system. we can figure out the chemistry and physics and without their that we see and then vice versa. >> guest: this is has been the idea. now i think in the book i tried to make the case that this is very interesting and it's lovely and an intriguing idea but it's rather limited because it doesn't tell you how much life there should be. you only need one instance of life to be able to make that sort of argument. we couldn't be here at the stars weren't a certain way and the fundamental physics work a certain way. great, but what is determining how much life there is in the

universe? perhaps have a clue that's a clue to something beyond what we have thought about and something deeper still and that's one of the other motivations for learning the abundance or frequency of life is. in the book i talk a little bit about how we might do that and i gloss over the details of what would be an extraordinary technological experiment. >> host: does this have to do with the calculation of uncertainty? i thought your discussion it was fabulous in the book because i'm no mathematician but i thought you did a great job doing that. >> part of the book is also about the way in which we deal with probability, the way in which many we make inference about the world around us based

unlimited information. >> host: because that's what we have here limited information. >> guest: absolutely in these days we rely in general very happily on a mathematical theorem that comes from this mathematician back in the 1600 1600's. his theorem is all about weighing evidence with query and asking not so much is my theory correct but how probable is it if my theory is correct given the observation that i've made and in the book i use a little allegorical tale to give an inference for how this works. the tale is about a baby that's going to turn into a rooster. attaches one day and it sees this thing in the sky which is

the son and that watches the sun move through the sky during the course of his first day in the world and its upset. it's an intelligent little and it thinks well is it going to come back again? the formulates as thomas base would a theory. i think there's a 50/50 chance and that's my theory. i will wait and see what happens. then the next morning the sun comes up again. >> host: that's another piece of data. >> guest: another piece of data as of now this can update its very a little bit with this new theory that says i'm going to change the odds of coming back again. and again again. consider instead of it being 50/50 i'm going to say 75/20. probably something will reappear. nothing does so after a month or

so the has gotten to the point where it has a 99% confidence that it will reappear in every day it's modified the theory. i don't know for sure that it will reappear but it's 99% sure. it's not crowing in the morning and annoying all the neighbors but this is the kind of approach answering scientific questions that are central to bayes theorem and modern science. the interesting thing about it is these are the questions that are difficult to answer otherwise. for example and i discussed this in the book, we do have a piece of evidence in the question of whether or not life is proper and that is that we are here. most scientists will say -- and they are right but it means

intuition says if i'm walking down the street and i bump into someone often people will say we are here and it's a really big universe and we know there are billions of planets everywhere. surely there has to be life somewhere else in the universe. it makes sense, right class well, not really. if you apply the way of looking at things that thomas bayes gave the idea for probability and inference and updating your theory with data it turns out there's there is this theory that life on earth started quickly a few billion years ago in a few billion liters along came organisms capable of making that observation. does not tell us about how life arrived elsewhere?

and the disappointing yet brain cancer is it actually tells you almost nothing about the likelihood of life elsewhere. in the book i use this to really emphasize the point that right now, if we can discover one single instance of life with an independent origin it would change everything. it wouldn't just be oh yes okay. it would actually change the numbers. updating the probability for the sun to come up again and in this case it narrows the option much more than with the and the sun. it would give you a much stronger likelihood of an enormous abundance of life in the universe if you write out the probabilistic formula.

>> host: so what of her time spent so far to gather this much-needed data? there was a project to scan the skies for radiofrequency and you talk about the signal in the book and various other ways. how might we go about getting this information collects. >> guest: i think there are several approaches tonight to get to the one we are talking about. the chemical signature, sifting in the dirt to look for some signs that they're up in life. not a practical approach and the principle beauty of that approaches you can begin to eliminate certain environments. we don't find anything, that's important and that will tell us something. there's another way to do this which you alluded to with the

wow signal. the wow signal was perhaps some people would consider the best example ever of a possibly artificial signal arriving on earth from somewhere else out there. it happened in the late 1970s and it was part of a project that was listening for extraterrestrial intelligence and the search for extraterrestrial and life. originally it was listening for radio signals and the idea was that you scanned the skies as much as you can with as many different radio frequencies as you can as many times as you c can. looking for things that don't appear to be natural in other words not coming from a star or

galaxy but there some structure to them. the kind of thing that we might send out into the universe whether intentionally or unintentionally. these days that's still an effort that's ongoing although it's been very difficult for them to raise money. it's the ultimate longshot. if you succeed. those who use a wow. >> guest: you say wow exactly. people say why are you doing this? i personally support the answer because it's one of those things you don't know. we simply don't know and if you don't listen you'll never find out. it may be extremely difficult to did detect something but again if you don't try you have absolutely no idea and if you try at least there's a slim chance. these days there's attention being paid to other forms of

study. for example optical seti. radio waves in space may not be the best way to either send signals across to other civilizations or to pick up random signals coming from civilization. radio waves can get distorted by the material that's actually out there between the stars in our galaxy. where is in the visible part of the spectrum the optical spectrum principles can send signals that are much more coherent. a big laser beam or some device. there's increased interest in looking for their interesting ideas that are bubbling up now that have to do with looking for some of the consequences of the technological civilization

and -- post go here we are not going for bacteria. this is the real deal. >> guest: one idea is that assuming and there are many functions, we are extrapolating an enormous amount from our own nature. civilizations and intelligent organisms built machine machines and they came up with ways to extract energy from the equivalent of gasoline or maybe nuclear power or solar-powered. maybe it's electrical, and maybe it's chemical. the consequence of energy use is you own the environment and for example you turn on your computer and it gets warm. what's that? that's just excess. that's just leakage from all the

things that are happening with the silicon chip inside of your computer. except now if you run the numbers in the civilization perhaps a bit bigger than we are able to generate a significant infrared signature. unintentionally. even if it's very efficient. energy is never destroyed. it's just transferred but it's very hard to get rid of this wasted energy. people are talking about could you build a telescope specifically designed to look for this infrared blip of a planet. little infrared light from a planet that can't be explained by any known natural phenomenon. there are the things that might generate heat signatures but the argument is there maybe a specific heat picture of civilization of technological life.

this is really a long reach, okay? but the interesting thing about it is that if we take this question really seriously it's actually the kind of thing we should be doing. we should be thinking about it. to come back to the earlier question about how are we going to evaluate our true significance, it's going to be a technological achievement rather than a philosophical one i think. >> host: when you conclude the book was sort of a subtle distinction between the uniqueness and significance, you explain the line you were working at the end and tell readers what to think about all of that? >> guest: i think i'm pretty honest in the book about saying this is my personal take. i've tried to put together all these different threads trying

to express where do i get to and put away think is the answer and part of what helps us get to a conclusion is that i often talk about how life is a phenomena of this edge between altering chaos. a thing that seems to emerge where there's a bit of energy but not too much energy in their certain chemicals but not too many chemicals and not that too few chemicals kind of an emergent phenomena which is the topic these days for this emergence. the idea is that a set of nuclear interacting things can somehow give rise to great life. like watching a flock of birds flying around. each individual bird would seem to be flying around but when you see a swooping flock of a swooping flock of birds in the sky takes on a huge difference structure.

i think that is a key piece of trying to pull these threads together. the conclusion that i give the reader in the book is that i think the way to reconcile the piece of evidence that don't quite fit together is to say that we may be unique but not exceptional. in other words, life on earth including gas maybe i'm like that anywhere else in the universe. but there may be also many other places that aren't totally unique. part of life through the last 4.5 billion years is full of twists and turns of the idea that you would end up with anything like us were creatures around us today again somewhere in the universe is very very unlikely and a very low probability.

>> host: something that might be equivalent if not identical. >> guest: this is it though, what is equivalent in here too we may not have enough information tending to think that the planet is occupied. they are creatures and yet they use coconut shells. they have been around for a long time. there are clearly survivors daren't evolution has paid off. at that map -- may not be alien enough. >> host: so as an editor in scientific american mind i have to ask, do you live your life as a cosmologist and you are constantly thinking so i wonder about that. because people who suffer from mental illness impaired anxious type and always looking a away and i was thinking about themselves.

i wonder if there are sort of a mental health value in having a broader view, right? we talk about are significant as being very important to us but sometimes we pay ourselves too much attention. almost seeing that it's more of us out there. thinking about the solar system and the universe may actually give some perspective. i wonder what you thought about that. >> guest: i would like to say i'm a shining example of being rational but i'm not sure. for me personally absolutely. this perspective is per from important to me. on the occasions where i pause and think about it and many

scientists as well the sense of wonder and the sense of curiosity, the sense of significance all add up to the package is kind of comforting. in a strange way. you would think you would be screaming in a darkened room but i think it actually makes you feel that i'm in this extraordinarily wonderful situation with so much around me and yet i'm utterly insignificant. but now that i'm sitting here thinking about it there something about that ability that extraordinary juxtaposition. i'm insignificant yet here i am capable of acknowledging it. >> host: if you are insignificant then maybe the problem with your toilet is also fairly insignificant.

>> guest: yeah. obviously it's hard to lead your life day-to-day we have to pay the bills. >> host: you can always be thinking about the universe. >> guest: right, to me it's a very proving idea that all this is merely a blip on a grander scheme. >> host: thank you very much. you have written an absolutely beautiful book. i was impressed by it both answering questions and writing. >> guest: thank you very much. it's been a pleasure. >> host: likewise. >> that was "after words" booktv's signature program in which authors of the latest nonfiction books are interviewed by journalists, public policymakers and others familiar with their material. "after words" airs every weekend

on booktv at 10:00 p.m. on saturday, 12 and 9:00 p.m. on sunday and 12:00 a.m. on monday. you can also watch "after words" on line. go to booktv.org and click on "after words" in the booktv series and topics list on the upper right side of the page. next on the national press club in washington d.c. john yoo author of "point of attack" and bruce fein author of "constitutional peril" debate war and foreign-policy views of drones and the meaning of the constitution. this is about an hour and a half. >> welcome everyone. tonight the committee for the republic is hosting a debate on war and the constitution

have been here engineering the