Lewis Dartnell: “The Knowledge: How to rebuild our world from scratch” | Talks at Google

afternoon, everyone. Thank you all very
much for coming along. My name’s Lewis. I’m a research Fellow up at
the University of Leicester, although I commute
from North London up to Leicester every day. And I completed my
PhD a couple of years ago just down the road at
University College London, UCL. And the field of
my actual research, my day job in the
science labs, is in a new field of research,
a new field of science, called astrobiology,
which is all about looking at the possibility of there
being life beyond the Earth. So I come from a
biological background, and in the last
couple of years got an enormous amount of planetary
science, and particle physics, and computer modeling,
and mathematical analysis techniques to look into
the big question about whether there’s life out
there, if there’s, perhaps, bacterial life on
the surface of Mars. And what I’ve been thinking
about for the last two years, for this new project, the
hobby I’ve been doing along the side, for this new
book, “The Knowledge: How to Rebuild Our
World from Scratch,” is on something
completely different. I’ve gone from the science and
helping the hunt for aliens to talking about how you
might reboot civilization from scratch. And this is the starting
point of a thought experiment. Let’s say that
this has happened. There’s been some kind
of global catastrophe, some kind of doomsday event,
some kind of apocalypse. And you’ve woken up, let’s say
with a hangover, the morning after the day before, the
day when the world as we know it has ended. And you’ve kind of
picked yourself up from the rubble and dust off
the dust, dust yourself off. And you’ve fallen in with
a crowd of other survivors. You’re in a kind of
post-apocalyptic world with a community of survivors. And this is the
kind of trope that I think we’re all pretty
familiar with already. This has been in plenty of
cinema films and sci-fi novels, from “I Am Legend” to “The
Road” or “The Death of Grass.” There’s a good
history of this kind of post-apocalyptic narrative. But the question that
I’ve been trying to ask is what to do next. What happens now? How can you pick
yourself up, right from the basics, from
the very fundamentals, and rebuild a
technological civilization from the ground up? What kind of stuff do you need? What kind of fundamental
processes and principles would you need to know? What would you want to have
condensed down to a single book that you’d want to
have handed to you in this post-apocalyptic world
that told you how to rebuild, how to reboot the civilization? And the conceit is that
that’s the book in your lap right now, that “The Knowledge”
is this single tome that tells you how to
redo or rebuild all the functions of a
modern civilization, of a technological civilization. And the reason I wrote this is,
first, I was fascinated by it. It’s an interesting thought
experiment to go through. But I think it’s also quite
relevant and perhaps topical, especially right now. Because I get the sense that
all of us in the modern world today have this kind of
feeling of disconnect, that we don’t really have
that much of a real sense, real understanding,
and certainly no hands-on,
practical experience of how a lot of stuff
is really done or how things are made in the
modern world today. And if you really had
to, let’s say if you’re in this post-apocalyptic
scenario, if you’re knocked back to
first principles, do any of us really have the foggiest idea
how to take a handful of seed and walk out to a
muddy field and make food come out of that field? How do you reinstate
agriculture? What are the
fundamental principles you need to know to
reinstate farming? Because it is not as
simple as you might think. Farming is a ludicrously
artificial process you have to go through. Even though plants
grow naturally, it is not in nature’s
best interest, if you like, to have
a monoculture of all the same crops growing
in very high density all in the same place
and not have it hit by disease or by pathogens
or pests or something. You’re trying to
rigorously control the ecology of a farm, a field
to grow food for yourself. So how do you do that? How do you get
metal out of rocks? How do you make the materials
that we rely upon today? If you can reach
into your pocket now, there are probably a
combination of metals, and plastics, and then
perhaps some glass. How do you make
that for yourself? How do you dig raw
substances, base substances, out of the ground, and then
process them or transform them into the materials
which are most useful? How do you go from
a raw material to something which
is useful, that you can use for a function? And this is what I’ve
been trying to talk about. This is the research I’ve
been doing for “The Knowledge” and trying to piece
together, chapter by chapter, these different themes of
communication technologies and transport technologies
and mechanisms and substances and chemicals. And the very
beginning of the book is playing around
with this idea of what I call the “grace period.” Because if there were to
be some kind of– let’s say that the best possible
way for the world to end would not be an asteroid
strike or a nuclear war, because it would leave
the world in tatters. You’d find devastation
around you, and it would be very, very
hard to reinstate farming when the fields
themselves are poisoned, when there’s radioactivity
from the fallout. So the starting
point for the thought experiment that I
picked up on, the best possible way for
the world to end was some kind of viral pandemic,
perhaps something like avian flu or swine flu, that
spreads incredibly quickly, with our high-density,
urban lifestyles today and intercontinental flights and
transmission of diseases very, very readily. And it wipes out 99.99%
of the world’s population. So the people have
gone, and there’s only a small community
of survivors left. But the stuff is still here. You can still go and
scavenge in a city and get the glass,
and the metal, and the timber and stuff
you need to repurpose and rejig and jerry-rig
stuff to keep yourself going. So the first chapter of the
book is talking about this grace period, how you get this
buffer zone, if you like, where you get a couple
of years, perhaps, maybe a couple of decades, maybe
a generation to work things out for yourself, to go through
this process of trial and error before it becomes a
mater of life and death to grow food for yourself. And one of the calculations
that I sat down and scratched my head was a sub-thought
experiment, if you like. If you were to be locked
in an average supermarket with fresh water, unlimited
fresh water, a way of disposing of your waste, so kind
of sanitary conditions, how long could you survive
in an average supermarket before you starved to death? How long would the food in the
supermarket sustain you for? And so clearly
you’d want to plan, play some kind of
optimal strategy. You eat the fresh fruit
and bread [INAUDIBLE] first, because they’ll
go in a matter of days, perhaps a week or two. You could then move on to the
dried pasta and the rice, which have a persistence time of
several months to years. And the largest reserve
of preserved food would clearly be tin cans,
would be the canned food. So I went around an
average supermarket, which was the one in
[? Angel Islington, ?] and I noted down and counted up and
multiplied up all the food that was in there, and
knowing the persistence times of each category
of food, and worked out that you could support
yourself for 55 years living on the sustenance of just
a single supermarket. And that would go up
to 63 years if you don’t mind eating the cat
food and the dog food. [LAUGHTER] LEWIS DARTNELL: So you’ve
got time to play with. If you multiply it out to
the society as a whole, to the stored sustenance
of the United Kingdom, the nation as a whole, for
a small community of perhaps several thousand, maybe a few
tens of thousands of people, you’ve got decades before
that food would run out, and you’d have to work out
the principles of farming to keep yourself going. Water, of course, is going to
be another primary consideration for you, and it goes by
repurposing everyday substances you can scavenge from the dead
cities, the abandoned cities. You can purify water very,
very adequately using something like kitchen bleach or swimming
pool chlorine, so sodium hypochlorite and
calcium hypochlorite, and you just dilute them enough. And this is exactly
the compounds they use in the public water
supply to purify water for you. Or even more simply
than that, all you need is an empty plastic
bottle, like this one here, and you fill it with water
and leave it in the sun. And then there’s a process
called solar disinfection, or SODIS, which is
recommended by the WHO, by the World Health
Organization, in the third world as a tried
and tested method for purifying drinking water for the very
simple and fundamental reason that the last thing you
want to catch in a world without antibiotics is a really
simple infection that could be prevented by just having
your wits about you and being aware of germ
theory and basic hygiene. So use SODIS to purify
drinking water for yourself by just scavenging some
empty plastic bottles. And you’d want to keep an
electrified lifestyle going for you. This is a car alternator. You can rip out
the bonnet of a car and jerry-rig them to some kind
of windmill or water wheel, turn the spindle, and
regardless of what speed you turn that spindle,
if you generate 12 volts across the tunnels,
you can recharge deep cycle batteries, which you
can scavenge from things like golf buggies or
yachts or RVs or caravans. They’re the best kind of battery
for storing power long-term compared to a car engine. And what I keep trying
to do in the book is come back to real
examples in our own history where similar scenarios
have occurred. And this is a city
called Garazda, which was cut off in
the Bosnian-Serbian war by the Bosnian army. And they had food
drops and medical drops from the Red Cross, but
they were completely isolated from the
national grid, from power. It had no electricity. And so they jerry-rigged, they
bodged, and created these water wheels for themselves, using
scavenged car alternators with these wheels
turning the current, and from these platforms
they tethered to a bridge. So a lot of this you can root
back down into real examples. This isn’t just speculation and
arm waving for the sake of it. There are some really
great examples. And I’ve come back to
POW camps a couple times where people have
bodged stuff together, things they can scavenge
from around them. If you want to keep your
cars going after the diesel and petrol has run
out, there’s a process known as gasification. And I’ve got a very short
video to show you in a second. But this is my gasified
stove that I made for myself for this video that’s up on
YouTube and on the book’s website as well. And this is, again,
ludicrously simple. It’s just a big,
[INAUDIBLE] tin can, with some holes around the
bottom, a smaller tin can in the middle, again, with
some holes at the bottom. And when you put your fuel,
your bits of wood in there, the holes at the bottom draw in
through the air and the oxygen, and it burns nice and intensely. But that’s kind of
what we’re familiar with from any barbecue. What’s novel about
these gasified stoves is you have a ring of
holes at the top as well, and that draws in
fresh oxygen, which meets, is reintroduced, into
the hot gasses, the vapor, and the smoke, which
is itself combustible, is re-mixed with oxygen, and
you get secondary combustion. So it’s a very,
very efficient way of using the fuel in the stove. And I’ve got, as I said,
a very short video to show you that process. So let’s get this fired
up and see it working. I’ll load it up with some simple
kindle, kindling and tinder here with just some
newspaper and some dried twigs, which
we push down in here. If I light the
underneath with a lighter I’ve been able to scavenge– And if you think
that’s a massive cheat, the previous video
to this is how you can use things
other than lighters and matches to start a fire
if you can’t scavenge those. And you can use something
like a fire alarm to start the fire with
or a bottle of water to start a fire with. And when it smokes
at the start– That’s why the
epidemic [INAUDIBLE] for real in the room. –we’ll put a slightly
higher flue on it. And already, that’s
roaring away, with the air and the
oxygen being drawn up. So we’ll get that going
nice and intensely, burning down that fuel. And before I take off
this flue now– it’s also called a rocket stove,
perhaps for obvious reasons. If I take off that flue– So this is just from a
small handful of twigs. There’s very, very
little fuel in there. If you come in
here and look, you can see that upper
ring of air holes, there are jets of
flame coming out there where the oxygen’s
being drawn in and igniting all those producer
gases coming off from the wood as it undergoes
pyrolysis and gives off the vapor and the gas. And the smoke itself
is combustible. So burning all of that. It’s a very, very efficient
way of using the fuel. So I reckon that’s
about ready for cooking. And then I cook
some custard, which I’d opened in one of
the previous videos. And the reason this
is important is it allows you to build
a gasified stove, but that was more for the
process of demonstration, but you can also do
amazing stuff like this. This is a gasifier-powered car. This is a wood-powered car. And you basically have
the stove strapped in a big dust bin on the back. This is where you drive
that process of pyrolysis. You use the heat of
combustion to break down the complex molecules
of the wood, release those producer
gases and the vapors, which you then
simply just pipe down at the cylinders of your
engine, mix with oxygen, as would happen with
your carborator anyway, and then drive your
car based on wood rather than liquid fuels,
rather than fossil fuels. So this is the
kind of technology, and again this was done
very, very commonly in the Second World War. There were over a
million gasified vehicles in the Second World War. And the German army even had
a division of Panzer tanks that were
wood-powered, that were driven by these things
strapped to the back of them, because they were
facing such acute fuel shortages towards
the end of the war. So it’s this kind of
technology or resurrection of historical
techniques that you can use to keep yourself
going in the grace period of the apocalypse. But more interestingly,
to myself as a scientist, was this thought
experiment, this process of thinking how you could reboot
a civilization from scratch, how you would actually
go through the process of rebuilding everything
from the agriculture and the transport technologies
and the communication technologies and the
materials and the substances that all of our lives rely upon. And, as I said, we
don’t really have any direct sense
of how that works. And so clearly agriculture and
being able to feed yourself is one of the key fundamentals. These are the cereal crops. All humanity eats grass. The cereal crops are
all species of grass. And if you don’t
eat wheat directly, you’re eating something
fed the grain, and they’re giving you a steak. So we all eat grass. These three crops here,
the wheat, rice, and maze, have supported civilizations
throughout human history. The European, Asian, and
North American civilizations have all been founded on
those three staple crops. And in the book,
there’s a map of how to find the Millennium Seed
Bank, where you can rescue heirloom grains, seed
corn, to reboot agriculture if you can’t find
anything in the fields because it’s been too long,
given with the latitude and longitude coordinates. And it explains
later in the book how you can reinvent
those, how you can find out exactly where this
place is in the world. You need technology mechanisms
to harvest that grain for you. And one of the major features
of the history of civilization has been the application
of power and mechanisms and harnessing natural
power sources like water, or wind in this example,
to relieve civilization from having to use
your own muscles, from having to go out
into the field yourself or grind grain into flour
with just a pestle and mortar. And so the key components
of this windmill here are these millstones
at the bottom, which grind the grain into flour,
which you then make bread out of and then can consume that
nutrition from the grass that you’ve harvested. So in a sense then,
these millstones are a technological extension
of your molar teeth. They’re a way we’ve
invented to push beyond the limitations of our
human body and use technology to enhance it with
those millstones there. Pottery and being able to
cook food and ferment food is an extension of our stomachs. We’ve basically invented
external digestive systems. And there’s a whole load
of similar examples. And it’s not just
mechanisms you need to be able to
reinvent and reboot. The poster boy of the
Industrial Revolution was the steam engine and
these big bits of machinery and the fire and the
power behind it all. But just as importantly,
there’s been the application of chemistry, of creating
the substances needed to support civilization,
things like soda or nitrates for your fields. And this example
here, again, goes back to the gasified stove
and the uses of wood, where if you warm the wood,
it starts breaking down and gives off all these
very, very useful compounds. And before the 1900s, and the
application of coal, and then crude oil is the feed stop for
petrochemicals and everything that feeds into the
chemical industry today, it was all timber-based. This is the more
rudimentary basis you need to drop back down
to, to leapfrog to, and then start recovering
your capabilities. I wanted to show just two
other pictures, slightly more egotistical. Because a lot of with research
for this book in writing it, clearly wasn’t
just at the library or at home reading text
and digesting information. It was doing things for real
and getting hands-on expertise. And this is a day spent
in a 1700s blacksmith, working by a coke-fired hearth
with bellows pumping away, getting bits of
metal to be red hot, and then hammering
the life out of them on an anvil with a big
blacksmith’s hammer. And I created a steel knife
for myself from scratch. I transformed a blank
of steel into a knife, which I then, very
smugly, very gleefully, took home and cut some bread,
and some cheddar and made myself a post-apocalyptic
cheese toastie from scratch, and then discovered, immediately
afterwards, a ruinous crack in the handle of my knife
that I made from scratch. I’d done a pretty awful job. But the point behind
this though is that I now know how to go back
and try again and do better. And it’s that process
of reiteration, on a microcosm with
me making a knife for myself, a tool from scratch. It’s exactly the same
process that civilization’s gone through over
thousands of years, and you want to have some
kind of effort at least accelerating that process
to perhaps just a couple of generations or a
couple of centuries. And if you look on
the inside cover of the books in your
laps, I was really keen for the author photo to
not just be a digital photo that we snapped and chopped
into Photoshop and printed. This is a photo we
made from scratch. I went to the Fox Talbot Museum,
where photography was invented back in the 1830s, 1840s, and
we mixed up the silver chemistry ourselves. We made these compounds
from scratch, dumped them onto a plate of glass, exposed
in a very rudimentary camera with just a single lens up
front for a 16-second exposure. It is ludicrously
hard to hold something that doesn’t look like a
death grimace for 16 seconds without blurring. And what you can’t
see is behind my back, there is an
honest-to-God metal brace that clamps at the
base of your skull to hold your head as still as
possible so it doesn’t blur in this very, very
long exposure. And that’s the reason why most
photos of Edwardian gentlemen and Victorian
gentleman may look so funless and joyless because
they’re standing still, sitting still for 15 seconds
with a metal clamp behind them. The other interesting
thing to point out, the very simple
chemistry we’ve used here is much more sensitive
to ultraviolet radiation, UV rays from sun, from
the visible light. So this isn’t actually
what your eyes would see. It’s slightly distorted. And your lips come out as
being very white, very pale, because they
reflect a lot of UV. And you’re actually seeing into
a deeper layer of your skin, kind of into the
dermis, which is why it’s a bit more
blotchy and dark. But I was quite chuffed
to be able to create a photo for myself and of myself
for the back page of the book. There’s a website linked
into “The Knowledge” as well with a whole load
of content and the videos that we created I’ve
mentioned already. This is a video about
how to start fire using only things
from an IKEA shop. And they’re creating
fire blown out of one of their coat
hangers that I’ve found from someone
else and uploaded. So it’s been a lot of fun. I’ve enjoyed these
last two years. And the conceit, at
least, is that this is the one tome,
the one book you would need to reboot
civilization from scratch with all these different
functions of the modern world you would need to recreate. I said, there’s the website you
can explore for a little bit more information and detail
and a Twitter stream as well. But I don’t want to
drone on too long. I thought I’d just say some
things for 15, 20 minutes, and introduce a bit about
what the book goes on about. But for me, the most
interesting thing is talking to you about
it and hearing your ideas. What would be the most
crucial information you would want to
preserve if there were to be some kind of
apocalyptic scenario, and you’d have to right
back from scratch? What would be the
crucial information that you’d want to
have handed to you? So thank you, guys,
for listening. I’d say we do have some time
for questions or discussion or chat. MALE SPEAKER: Thank
have a microphone. Does anyone have any questions? Right in the back. AUDIENCE: Thank you. That was very, very interesting. So one of the questions was–
so all that knowledge and how to do all those things
right now is preserved on things like YouTube and
digital books and things that. How can we make sure that we
don’t lose that knowledge so that we can actually do those
things when we get to that day? LEWIS DARTNELL: Well,
a very similar problem was encountered in the
latter half of the 1700s when the very first
encyclopedias were being compiled about people
like Dennis Diderot. And they came across a
very similar problem. How can you explain
practical skills like weaving, or making
nets, or harvesting, bringing in a harvest
in the fields? How can you explain these
very practical skills that you learn over the
course of many years, working with someone who
already knows how to do it and showing you and correcting
you if you’re doing it wrong? How can you communicate
and condense that into just words in an
encyclopedia or perhaps just some diagrams? And the only
encyclopedia compilers, and there’s a blog post on
exactly this on the website, they were acutely aware, perhaps
even more so than we are today, of just how fragile and
vulnerable civilizations are. The Roman Empire collapsed, the
Greek civilization collapsed, the Mayans and Incans, which
we’ve discovered subsequently, have all collapsed. So what could you do
to preserve the sum total of human knowledge? And they made genuine attempts
to record everything back then. We know a bit more
nowadays, so that would be perhaps impossible, and
even something like Wikipedia doesn’t even come close. So the conceit, the kind of
cheeky answer, if you like, up the website is you would
get an iPad or another kind of tablet, you would
jerry-rig with a solar panel or an alternator from a car to
regenerate power for yourself and recharge your
batteries, and you would download some of
the apps I recommend. We can rip off, scoop
off videos from YouTube, and save them on this
hard disk of your tablet. So when the internet goes
down, which will happen very, very quickly after the
apocalypse, you’ve still got, not just the words of
“The Knowledge” book, but also these
kind of demo videos stored for prosperity
as it were. AUDIENCE: Well, I was
just going to ask, do you think we might
have been in a better position to reinvent [INAUDIBLE]
maybe a hundred years ago before the internet? Because the internet
makes people’s minds lazy, and you don’t have
to know stuff, because you can look
it up on the internet. And so, therefore, that’s how
civilization spread early, orally being passed down from
generation-to-generation, skills, stories,
mythologies, et cetera. LEWIS DARTNELL: Yeah,
my gut reaction, my impression is that we’d
probably be worse off today than a century ago if this
hypothetical scenario were to happen, if you do have
to go back to scratch. Because even during
the Second World War, there was an enormous amount
of ingenuity and problem solving during the scarcity
of the Second World War, and most people had an
allotment in the back garden, and they grew stuff themselves. They grew vegetables and
food to feed themselves. How many of us do that today? No. There’s perhaps not
that many hipsters in London that have even
got access to an allotment to be able to grow. And I did try when
I was living down in Angel to get an
allotment for myself, and there was something like
a nine-year waiting list. So all of these skills
are just dissolving away. They’re disappearing. You don’t repair things
for yourself anymore. You can’t get your
radio and take out the valve that isn’t working
anymore and replace it. You can’t look and understand
the mechanism of the things we use, because– You know, your iPhone,
the mechanism inside that is literally visibly small. You’d need a microscope to be
able to see the kind of city landscape of the
circuitry there. And it’s not something that you
could ever repair for yourself. And in fact, you’re
not even expected to take the back off
technology nowadays. You just take it
back to the shop, and a genius will
repair it for you. And I think that’s sad. I think it’s lamentable we’re
losing that connection with how things are made or done
in a fundamental sense. AUDIENCE: Thanks. Really interesting talk. LEWIS DARTNELL: Thank you. AUDIENCE: Thank you. Two related questions. As you went through all
of your research for this, and you were focusing on
things that we were missing, were there any kind of objects
or processes that you thought, you know what? Actually, we could
just forget that. And kind of related to that,
are there any social constructs that you came across that you
thought how would we implement law or government
or whatever it is? LEWIS DARTNELL: Yeah, so,
two very good questions. One of the recurring themes I
tried to keep coming back to through the book
was this network, this web of scientific
discoveries, which enable you to make new
technological innovations, which then allow
you to investigate the world in a new way and make
new scientific discoveries. So that kind of back-and-forth
process between science and technology and exploring
this vast web of knowledge we have today. So for example, mastering
the substance of glass and grinding it into a
lens to build a microscope, which allows you to explore
the invisible realm. But with hindsight, we
now know red herrings we took in history, science,
and technology, or stuff that turn out to be not all
that very useful, or things like electricity that
are so useful in so many different ways you
want to beeline directly to that gateway
technology, as I call it, and it opens up a whole
load of other stuff. So there’s a video about
electrolysis on the website, about how you can use
electricity not just for power and moving things
with motors for you, but generating
crucial substances, like bleach or
chlorine and things. So you want to leapfrog
something like electricity and the printing press
for similar reasons and also the social
ramifications of that. But, it being a
popular science book, and already being
quite difficult to fit all the scientific knowledge
into just 300 pages, one of the early decisions,
one of the early editorial decisions was to leave out
more of the social sciences, the politics and economics
and a description of how to build a
democracy from scratch. Because, while undeniably
important, I think there’s a clear distinction
between art and music and politics and science, and
that science is universal. The laws will be true no matter
where you are or when you are. Humanity will have the same
requirements and demands that technology
must provide for. So science and technology,
in a sense, are universal, but politics isn’t really. And my suspicion was if I wrote
this twee little 10-step guide to building a parliamentary
democracy, it doesn’t matter, because whoever’s
got the biggest gun gets to be the boss anyway. And they’re not going to
relinquish their power unless you go
through, perhaps, 100, 200 years of social
revolution and slow change. So you can provide key kernels
or principles of science, but you can’t really do the same
thing for social constructs. I think they have to arise
organically or naturally. And it probably wouldn’t
make that much difference if you described democracy,
because it would– no one would pay any attention unless
they’re ready for it anyway. You’d perhaps live
with a feudal system for 50 years or whatever. MALE SPEAKER: Time for one more. AUDIENCE: So, thanks
for presenting, and thanks for the book. I’ve been waiting for
something like this since I discovered
science fiction, because, all these post-apocalyptic
scenarios, it’s good to know that now we
know how to fend for ourselves. Personal question for you. If the apocalypse in
the way you described came, and 99.99% of the
population with decimated, beyond locking yourself up in a
supermarket for food and water for the next 55
years, what would be your personal next steps? Medicine? Go and find the biggest gun? Something else? LEWIS DARTNELL: Yeah, so
there’s been a bunch of reviews on the Amazon US site,
and there’s allegedly been a bunch of preppers
who have reviewed this book about
rebuilding civilization. And they just love their guns. And one of the
major questions is, you haven’t talked about
weaponry in your book. And, of course, it’s true. But again, the resounding bottom
line is, if you’ve got a gun, you’re fine. If you don’t have
a gun, find one. It’s not an
interesting discussion. There’s no interesting
answer to be had there. And the knowledge isn’t
going to help you either way. So I avoided guns right
from the beginning, for the same reason I avoid
the politics and stuff. But clearly, for this
book to be relevant, you have to be in a world
that isn’t like “The Road.” You have to be
beyond that stage. This is what happens next. And you have got some
semblance of stable society, where people are now
ready to start progressing and rebuilding, as
happened in 1340s after the bubonic plague
and the Black Death. A lot of people died. People shrugged their
shoulders, stiff upper lip, and got on with it. So the next step, the
one piece of information that I think would be most
critical out of all knowledge that you would really want
to preserve and not forget, I’ve hinted at
already, is this idea of germ theory and hygiene. There is nothing you can do more
for yourself to keep yourself healthy and alive than
stopping yourself picking up a transmissible infection
in the first place. And the basic tenets of
germ theory and hygiene are what will really
help you out there, when there aren’t
antibiotics anymore. So, we aren’t
being too prurient. Make sure you’re not
drinking your own excrement, making sure no one else
is putting excrement into the river where you’re
taking your water from. And you laugh now, and this is
obviously a disgusting thing. As late as the
1850s, 1860s, that’s what happened in London,
the capital of the most powerful empire
in the world, they were pouring their poo
into the River Thames, and someone else 20 yards
down the road, down the river, was pulling up a
bucket and drinking it. And tens of thousands
of people would be dying in a week with
cholera, but for really easily preventable ways. So one of the key
technologies I talk about is how to make a microscope,
ludicrously simple, to prove to yourself that
there are these organisms, that are too small to see
that cause disease, and you want to break that
cycle with things like hygiene. It demonstrates
scientifically, with evidence, why this is important. [INAUDIBLE] I think Rob is going
to drag me onto the tube to– MALE SPEAKER: Yeah, we’re
going to go to [INAUDIBLE]. LEWIS DARTNELL: To
your other main site. MALE SPEAKER: So, please, join
me in a round of applause. Thank you, Lewis Dartnell. LEWIS DARTNELL: Thank you, guys. [APPLAUSE]