here in oxford in the nineteen seventies the future of the world was bleak
the population explosion was unstoppable global famine was inevitable a cancerepidemic caused by chemicals in the environment was going to shorten our lives
the acid rain was falling on the forests the desert was advancing by a mile or two a year the oil was running out and a nuclear winter would finish us off
none of those things happened
and astonishingly if you look at what actually happened in my lifetime the average per capita income of the average person on the planet in real terms adjusted for inflation has
how did we achieve that whether you think it's a good thing or not how did we achieve that how did we become the only species that becomes more prosperous as it becomes more populous
the size of the blob in this graph represents the size of the population and the level of the graph represents gdp per capita i think to answer that question you need to understand how human beings
bring together their brains and enable their ideas to combine and recombine to meet and indeed to mate in other words you need to understand how ideas have sex
i want you to imagine how we got from making objects like this to making objects like this
both exactly the same size and shape to an uncanny degree i've tried to work out which is bigger and it's almost impossible
and that's because they're both designed to fit the human hand they're both technologies in the end their similarity is not that interesting it just tells you they were both designed to fit the human hand
made the same tool for thirty thousand generations of course there were a few changes but tools changed slower than skeletons in those days
there was no progress no innovation it's an extraordinaryphenomenon but it's true whereas the object on the right is obsolete after five years
and more than that it's a confection of different ideas the idea of plastic the idea of a laser the idea of transistors they've all been combined together in this technology
and it's this combination this cumulative technology that intrigues me because i think it's the secret to understanding what's happening in the world
my body 's an accumulation of ideas too the idea of skin cells the idea of brain cells the idea of liver cells they've come together how does evolution do cumulative combinatorial things well it uses sexual reproduction
in an asexual species if you get two different mutations in different creatures a green one and a red one then one has to be better than the other one goes extinct for the other to survive
but if you have a sexualspecies then it's possible for an individual to inherit both mutations from different lineages so what sex does is it enables the individual to draw upon
the genetic innovations of the whole species it's not confined to its own lineage what's the process that's having the same effect in culturalevolution as sex is having in biological evolution
and i think the answer is exchange the habit of exchanging one thing for another it's a unique human feature
no other animal does it you can teach them in the laboratory to do a little bit of exchange and indeed there's reciprocity in other animals but the exchange of one object for another never happens as adam smith said no made ever saw a dog make a fair exchange of a bone with another
you can have culture without exchange you can have as it were asexual culture chimpanzees killer whales these kinds of creatures they have culture they teach each other traditions
which are handed down from parent to offspring in this case chimpanzees teaching each other how to crack nuts with rocks but the difference is that
these cultures never expand never grow never accumulate never become combinatorial and the reason is because there is no
sex as it were there is no exchange of ideas chimpanzee troops have different cultures in different troops there's no exchange of ideas between them
adam takes four hours to make a spear and three hours to make an axe oz takes one hour to make a spear and two hours to make an axe so oz is better at both spears and axes than adam he doesn't need adam
can make his own spears and axes well no because if you think about it if oz makes two spears and adam make two axes and then they trade
then they will each have saved an hour of work and the more they do this the more true it's going to be because the more they do this the better adam is going to get at making axes and the better oz is going to get at making spears
so the gains from trade are only going to grow and this is one of the beauties of exchange is it actually creates the momentum for more specialization which creates the momentum for more exchange and so on
adam and oz both saved an hour of time that is prosperity the saving of time in satisfying your needs ask yourself how long you would have to work to
how long do you actually have to work to earn an hour of reading light if you're on the average wage in britain today and the answer is about half a second
go back to this image of the axe and the mouse and ask yourself who made them and for who
axe was made by someone for himself it was self sufficiency we call that poverty these days but the object on the right was made for me by other people
how many other people tens hundreds thousands you know i think it's probably millions because you've to include the man who grew the coffee which was brewed for the man who was on the oil rig who was drilling for oil which was going to be made into the
and that's the way society works that's what we've achieved
as a species in the old days if you were rich you literally had people working for you that's how you got to be rich you employed them louis xiv had a lot of people working for him they made his silly outfits like this and
they did his silly hairstyles or whatever he had four hundred and ninety eight people to prepare his dinner every night but a modern tourist going around the palace of versailles and looking at louis xiv 's pictures
he has four hundred and ninety eight people doing his dinner tonight too they're in bistros and cafes and restaurants and shops all over paris and they're all ready to serve you at an hour 's notice with an excellent meal that's probably got higher quality than louis xiv even
and that's what we've done because we're all working for each other we're able to draw upon specialization and exchange to raise each other 's living standards
now you do get other animals working for each other too ants are a classic example workers work for queens and queens work for workers but there's a big difference
which is that it only happens within the colony there's no working for each other across the colonies and the reason for that is because there's a reproductive division of labor
that is to say they specialize with respect to reproduction the queen does it all in our species we don't like doing that it's the one thing we insist on doing for ourselves is reproduction
even in england we
so when did this habit start and how long has it been going on and what does it mean well i think probably the oldest version of this is probably the sexual division of labor but i've got no evidence for that it just looks
like the first thing we did was work male for female and female for male in all hunter gatherer societies today there's a foraging division of labor between
on the whole hunting males and gathering females it isn't always quite that simple but there's a distinction between specialized roles between males and females
and the beauty of this system is that it benefits both sides the woman knows that in the hadzas case here digging roots to share with men in exchange for
and the man knows that he doesn't have to do any digging to get roots all he has to do is make sure that when he kills a warthog it's big enough to share some
and so both sides raise each other 's standards of living through the sexual division of labor when did this happen we don't know but it's possible that neanderthals didn't do this
they were a highly cooperativespecies they were a highly intelligentspecies their brains on average by the end were bigger than yours and mine in this room today
they were imaginative they buried their dead they had language probably because we know they had the foxp two gene of the same kind as us which was discovered here in oxford and it looks like they probably had linguistic skills they were brilliant people i'm not dissing the neanderthals but
there's no evidence of a sexual division of labor there's no evidence of gatheringbehavior by females
it looks like the females were cooperative hunters with the men and the other thing there's no evidence for is exchange between groups because the
the same valley there are modern human remains from about the same date thirty thousand years ago and some of those are from local chert but more but many of them are made from obsidian from a long way away
and when human beings began moving objects around like this it was evidence that they were exchanging between groups trade is ten times as old as farming
as discovered by a team here in oxford moving one hundred and twenty five miles inland from the mediterranean in algeria and that's evidence that people have started exchanging between groups and that will have led to specialization
how do you know that long distance movement means trade rather than migration well you look at modern hunter gatherers like aboriginals who quarried for stone axes at a place called mt isa which was
so long distance movement of tools is a sign of trade not migration what happens when you cut people off from exchange from
the ability to exchange and specialize and the answer is that not only do you slow down technological progress you can actually throw it into reverse
an example is tasmania when the sea level rose and tasmania became an island ten thousand years ago the people on it not only experienced slower
progress than people on the mainland they actuallyexperienced regress they gave up the ability to make tools and fishingequipment and clothing
because the population of about four thousand people was simply not large enough to maintain the specialized skills necessary
to keep the technology they had it's as if the people in this room were plonked on a desert island how many of the things in our pockets could we continue to make after ten thousand years
it didn't happen in tierra del fuego similar island similar people the reason because
is separated from south america by a much narrower straight and there was trading contact across that straight throughout ten thousand years the tasmanians were isolated
go back to this image again and ask yourself not only who made it and for who but who knew how to make it
the case of the stone axe the man who made it knew how to make it but who knows how to make a computer mouse
the president of the computer mouse company doesn't know he just knows how to run a company the person on the assembly line doesn't know because he doesn't know how to drill an oil well to get
out to make plastic and so on we all know little bits but none of us knows the
i am of course quoting from a famous essay by leonard read the economist in the nineteen fifties called i pencil in which he wrote about how a pencil came to be made and how nobody knows even how to make a pencil
because the people who assemble it don't know how to mine graphite and they don't know how to fell trees and that kind of thing and what we've done in human society through exchange and specialization is
created the ability to do things that we don't even understand
but with technology we can actually do things that are beyond our capabilities we've gone beyond the capacity of the human mind to an extraordinary degree and by the way
that's one of the reasons that i'm not interested in the debate about i q about whether some groups have higher i q s that other groups it's completely irrelevant
what's relevant to a society is how well people are communicating their ideas and how well they're cooperating not how clever their individuals
so we've created something called the collective brain we're just the nodes in the network we're the neurons in this brain
it's the interchange of ideas the meeting and mating of ideas between them that is causing technological progress incrementally bit by bit however bad things happen and in the future as we go forward
we will of course experience terrible things there will be wars there will be depressions there will be natural disasters awful things will happen in this century i'm absolutely sure
but i'm also that because of the connections people are making and the ability of ideas to meet and to mate as never before
also sure that technology will advance and therefore living standards will advance because through the cloud through crowd sourcing through the bottom up world that we've created where not just the elites
but everybody is able to have their ideas and make them meet and mate we are surely accelerating the rate of innovation thank you
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