Imagine a brilliant neuroscientist named Mary.
Mary lives in a black and white room, she only reads black and white books, and her screens only display black and white.
But even though she has never seen color, Mary is an expert in color vision and knows everything ever discovered about its physics and biology.
She knows how different wavelengths of light stimulate three types of cone cells in the retina, and she knows how electrical signals travel down the optic nerve into the brain.
There, they create patterns of neural activity that correspond to the millions of colors most humans can distinguish.
Now imagine that one day, Mary's black and white screen malfunctions and an apple appears in color.
For the first time, she can experience something that she's known about for years.
Does she learn anything new?
Is there anything about perceiving color that wasn't captured in all her knowledge?
Philosopher Frank Jackson proposed this thought experiment, called Mary's room, in 1982.
He argued that if Mary already knew all the physical facts about color vision, and experiencing color still teaches her something new, then mental states, like color perception, can't be completely described by physical facts.
The Mary's room thought experiment describes what philosophers call the knowledge argument, that there are non-physical properties and knowledge which can only be discovered through conscious experience.
The knowledge argument contradicts the theory of physicalism, which says that everything, including mental states, has a physical explanation.
To most people hearing Mary's story, it seems intuitively obvious that actually seeing color will be totally different than learning about it.
Therefore, there must be some quality of color vision that transcends its physical description.
The knowledge argument isn't just about color vision.
Mary's room uses color vision to represent conscious experience.
If physical science can't entirely explain color vision, then maybe it can't entirely explain other conscious experiences either.
For instance, we could know every physical detail about the structure and function of someone else's brain, but still not understand what it feels like to be that person.
These ineffable experiences have properties called qualia, subjective qualities that you can't accurately describe or measure.
Qualia are unique to the person experiencing them, like having an itch, being in love, or feeling bored.
Physical facts can't completely explain mental states like this.
Philosophers interested in artificial intelligence have used the knowledge argument to theorize that recreating a physical state won't necessarily recreate a corresponding mental state.
In other words, building a computer which mimicked the function of every single neuron of the human brain won't necessarily create a conscious computerized brain.
Not all philosophers agree that the Mary's room experiment is useful.
Some argue that her extensive knowledge of color vision would have allowed her to create the same mental state produced by actually seeing the color.
The screen malfunction wouldn't show her anything new.
Others say that her knowledge was never complete in the first place because it was based only on those physical facts that can be conveyed in words.
Years after he proposed it, Jackson actually reversed his own stance on his thought experiment.
He decided that even Mary's experience of seeing red still does correspond to a measurable physical event in the brain, not unknowable qualia beyond physical explanation.
But there still isn't a definitive answer to the question of whether Mary would learn anything new when she sees the apple.
Could it be that there are fundamental limits to what we can know about something we can't experience?
And would this mean there are certain aspects of the universe that lie permanently beyond our comprehension?
Or will science and philosophy allow us to overcome our mind's limitations?
JR: Art is not supposed to change the world.
But art can change the way we see the world.
(Music) So now my wish is ...
for you to stand up for what you care about by participating in a global art project.
And together, we'll turn the world inside out.
[Great big story in partnership with TED] Narrator: They had a big idea to change the world.
But they couldn't do it alone.
(Voices overlapping) So, my wish ...
My wish ...
I wish ...
And now, here's my wish.
[Torchbearers] [Ideas in action] (Camera clicking) JR: My name is JR, I like to call myself an artist.
There are two ways of thinking about my work.
The easy way is just -- I'm papering black-and-white images on walls.
But I believe my work is about connecting people.
For me, it's the power of bringing people together.
I went there to do art projects with the community.
Now I realize that the community wanted to do art projects even more than I wanted.
And I started thinking: Why I don't take myself out of the equation and let them do it?
So the wish was pretty simple: we just put up a website and you can send us your photo for whatever you believe in or whatever you want to fight for; we'll send you back your photo in large format, wherever you are in the world.
Every day, I see rolls leaving around the world.
The project went much further than the places I've been, and that shows the power of art.
And the Photobooths truck is the magic of it.
(Music) Luana: We're a team of four traveling in the Photobooths truck: Josh, Basel, Jamie and I.
Jamie: To pose, they should look like this.
(Laughter) We are using two of these trucks to cover 30 cities around America.
Luana: We're just a tool for people that want to send a positive message.
Jamie: Step inside and take a seat over here.
Once the truck is ready and running, anyone can come.
Wait for the flash.
(Music) (Camera clicking) Touch the screen, take your picture, type in information.
In a matter of a minute or so, we print on the side, three by four feet.
No one is used to seeing their face so big.
Woman: Oh yeah, there's my funny face for you.
Jamie: The truck has this magic about bringing photography back to the print.
Then the posters go to the wall.
We use wallpaper glue, put them up and that's it.
We printed more than 300,000 faces already.
And we sent them to more than 130 countries.
(Music) Luana: It's the people's art project.
We don't decide the message.
It can be political, to bring attention to issues.
Jamie: I love the idea of using photography to promote change.
This specific project is to raise awareness about the DREAMers situation.
Karina Ruiz: INSIDE OUT is bringing the opportunity for DREAMers like myself, a person that came here at young age to have a better future, to come out and give a face to the issue.
Vianey Perez: When people drive by and they see a lot of faces, they're going to get curious and they're going to wonder who they are.
That's the face to the issue.
To humanize it.
(Music) JR: You do think that just pasting an image up there might have no impact, but it does have an impact.
You cannot know when and how, but it's worth trying.
Jamie: It all starts with believing.
Right?
And so, if you don't believe that you can make change, change will never happen.
Even if it's a very small change in one person, that's a positive change.
This is not about JR anymore.
It's about everyone who believes that art can change the world.
JR: I think that definitely art can change the perception we have about the world.
And if we start seeing the world differently, maybe it's a good path to start changing the world.
[Be a part of INSIDE OUT InsideOutProject.net]
Last year here at TED I asked you to give me your data, to put your data on the web, on the basis that if people put data onto the web -- government data, scientific data, community data, whatever it is -- it will be used by other people to do wonderful things, in ways that they never could have imagined.
So, today I'm back just to show you a few things, to show you, in fact, there is an open data movement afoot, now, around the world.
The cry of "Raw data now!"
which I made people make in the auditorium, was heard around the world.
So, let's roll the video.
A classic story, the first one which lots of people picked up, was when in March -- on March 10th in fact, soon after TED -- Paul Clarke, in the U.K. government, blogged, "Oh, I've just got some raw data.
Here it is, it's about bicycle accidents."
Two days it took the Times Online to make a map, a mashable map -- we call these things mash-ups -- a mashed-up user interface that allows you to go in there and have a look and find out whether your bicycle route to work was affected.
Here's more data, traffic survey data, again, put out by the U.K. government, and because they put it up using the Linked Data standards, then a user could just make a map, just by clicking.
Does this data affect things?
Well, let's get back to 2008.
Look at Zanesville, Ohio.
Here's a map a lawyer made.
He put on it the water plant, and which houses are there, which houses have been connected to the water.
And he got, from other data sources, information to show which houses are occupied by white people.
Well, there was too much of a correlation, he felt, between which houses were occupied by white people and which houses had water, and the judge was not impressed either.
The judge was not impressed to the tune of 10.9 million dollars.
That's the power of taking one piece of data, another piece of data, putting it together, and showing the result.
Let's look at some data from the U.K. now.
This is U.K. government data, a completely independent site, Where Does My Money Go.
It allows anybody to go there and burrow down.
You can burrow down by a particular type of spending, or you can go through all the different regions and compare them.
So, that's happening in the U.K. with U.K. government data.
Yes, certainly you can do it over here.
Here's a site which allows you to look at recovery spending in California.
Take an arbitrary example, Long Beach, California, you can go and have a look at what recovery money they've been spending on different things such as energy.
In fact, this is the graph of the number of data sets in the repositories of data.gov, and data.gov.uk.
And I'm delighted to see a great competition between the U.K. in blue, and the U.S. in red.
How can you use this stuff?
Well, for example, if you have lots of data about places you can take, from a postcode -- which is like a zip plus four -- for a specific group of houses, you can make paper, print off a paper which has got very, very specific things about the bus stops, the things specifically near you.
On a larger scale, this is a mash-up of the data which was released about the Afghan elections.
It allows you to set your own criteria for what sort of things you want to look at.
The red circles are polling stations, selected by your criteria.
And then you can select also other things on the map to see what other factors, like the threat level.
So, that was government data.
I also talked about community-generated data -- in fact I edited some.
This is the wiki map, this is the Open Street Map.
"Terrace Theater" I actually put on the map because it wasn't on the map before TED last year.
I was not the only person editing the open street map.
Each flash on this visualization -- put together by ITO World -- shows an edit in 2009 made to the Open Street Map.
Let's now spin the world during the same year.
Every flash is an edit.
Somebody somewhere looking at the Open Street Map, and realizing it could be better.
You can see Europe is ablaze with updates.
Some places, perhaps not as much as they should be.
Here focusing in on Haiti.
The map of Port au-Prince at the end of 2009 was not all it could be, not as good as the map of California.
Fortunately, just after the earthquake, GeoEye, a commercial company, released satellite imagery with a license, which allowed the open-source community to use it.
This is January, in time lapse, of people editing ... that's the earthquake.
After the earthquake, immediately, people all over the world, mappers who wanted to help, and could, looked at that imagery, built the map, quickly building it up.
We're focusing now on Port-au-Prince.
The light blue is refugee camps these volunteers had spotted from the [satellite images].
So, now we have, immediately, a real-time map showing where there are refugee camps -- rapidly became the best map to use if you're doing relief work in Port-au-Prince.
Witness the fact that it's here on this Garmin device being used by rescue team in Haiti.
There's the map showing, on the left-hand side, that hospital -- actually that's a hospital ship.
This is a real-time map that shows blocked roads, damaged buildings, refugee camps -- it shows things that are needed [for rescue and relief work].
So, if you've been involved in that at all, I just wanted to say: Whatever you've been doing, whether you've just been chanting, "Raw data now!"
or you've been putting government or scientific data online, I just wanted to take this opportunity to say: Thank you very much, and we have only just started!
(Applause)