Have you experienced déjà vu?
It's that shadowy feeling you get when a situation seems familiar.
A scene in a restaurant plays out exactly as you remember.
The world moves like a ballet you've choreographed, but the sequence can't be based on a past experience because you've never eaten here before.
This is the first time you've had clams, so what's going on?
Unfortunately, there isn't one single explanation for déjà vu.
The experience is brief and occurs without notice, making it nearly impossible for scientists to record and study it.
Scientists can't simply sit around and wait for it to happen to them -- this could take years.
It has no physical manifestations and in studies, it's described by the subject as a sensation or feeling.
Because of this lack of hard evidence, there's been a surplus of speculation over the years.
Since Emile Boirac introduced déjà vu as a French term meaning "already seen," more than 40 theories attempt to explain this phenomenon.
Still, recent advancements in neuroimaging and cognitive psychology narrow down the field of prospects.
Let's walk through three of today's more prevalent theories, using the same restaurant setting for each.
First up is dual processing.
We'll need an action.
Let's go with a waiter dropping a tray of dishes.
As the scene unfolds, your brain's hemispheres process a flurry of information: the waiter's flailing arms, his cry for help, the smell of pasta.
Within milliseconds, this information zips through pathways and is processed into a single moment.
Most of the time, everything is recorded in-sync.
However, this theory asserts that déjà vu occurs when there's a slight delay in information from one of these pathways.
The difference in arrival times causes the brain to interpret the late information as a separate event.
When it plays over the already-recorded moment, it feels as if it's happened before because, in a sense, it has.
Our next theory deals with a confusion of the past rather than a mistake in the present.
This is the hologram theory, and we'll use that tablecloth to examine it.
As you scan its squares, a distant memory swims up from deep within your brain.
According to the theory, this is because memories are stored in the form of holograms, and in holograms, you only need one fragment to see the whole picture.
Your brain has identified the tablecloth with one from the past, maybe from your grandmother's house.
However, instead of remembering that you've seen it at your grandmother's, your brain has summoned up the old memory without identifying it.
This leaves you stuck with familiarity, but no recollection.
Although you've never been in this restaurant, you've seen that tablecloth but are just failing to identify it.
Now, look at this fork.
Are you paying attention?
Our last theory is divided attention, and it states that déjà vu occurs when our brain subliminally takes in an environment while we're distracted by one particular object.
When our attention returns, we feel as if we've been here before.
For example, just now you focused on the fork and didn't observe the tablecloth or the falling waiter.
Although your brain has been recording everything in your peripheral vision, it's been doing so below conscious awareness.
When you finally pull yourself away from the fork, you think you've been here before because you have, you just weren't paying attention.
While all three of these theories share the common features of déjà vu, none of them propose to be the conclusive source of the phenomenon.
Still, while we wait for researchers and inventers to come up with new ways to capture this fleeting moment, we can study the moment ourselves.
After all, most studies of déjà vu are based on first-hand accounts, so why can't one be yours?
The next time you get déjà vu, take a moment to think about it.
Have you been distracted?
Is there a familiar object somewhere?
Is your brain just acting slow?
Or is it something else?
A few years ago, about seven years ago, I found myself hiding in a festival toilet, a music festival toilet, and if anyone's been to a music festival, yeah, you'll know that by the third day, it's pretty nasty.
I was standing in the toilet because I couldn't even sit down, because the toilet roll had run out, there was mud everywhere, and it smelled pretty bad.
And I stood there thinking, "What am I doing?
I don't even need the toilet."
But the reason I went was because I was volunteering for a large charity on climate justice, and it was seven years ago, when lots of people didn't believe in climate change, people were very cynical about activism, and my role, with all of my teammates, was to get people to sign petitions on climate justice and educate them a bit more about the issue.
And I cared deeply about climate change and lots of inequality, so I'd go and I'd talk to lots of people, which made me nervous and drained me of energy, but I did it because I cared, but I would hide in the toilets, because I'd be exhausted, and I didn't want my teammates doubting my commitment to the cause, thinking that I was slacking.
And we'd go and meet at the end of our shift, and we'd count how many petitions had been signed, and often I'd win the amount of petitions signed even though I had my little breaks in the toilet.
But I was always very jealous of the other activists, because either they had the same amount of energy as they had when they began the shift of getting people to sign petitions, or often they had more energy, and they'd be really excited about going to watch the bands in the evening and having a dance.
And even if I loved the bands, all I wanted to do was to go back to my tent and have a sleep, because I'd just feel completely wiped out, and I was really jealous of people that had the energy to go and party hard at the festivals.
But it also made me really angry, as well, inside.
I thought, "This isn't fair, I'm an introvert, and all of the offline campaigning seems to be favoring extroverts."
I would go on marches which drained me.
That was the other option.
Or I'd go and join campaigns outside embassies or shops.
The only thing that was on offer was around lots of people, it was very loud activism, it always involved lots of people, it was performing.
None of it was for introverts, and I not only thought that that wasn't fair, because a third to a half of the world's population are introverts, which isn't fair on them, because we burn out, or we'd be put off by activism and not do it, and everyone needs to be an activist in this world.
And also, I didn't think it was particularly clever, but I could see that a lot of the activism that worked wasn't only extrovert activism.
It wasn't only the loud stuff.
It wasn't about people performing all the time.
A lot of the work that was needed was in the background, was hidden, wasn't seen.
And when I ended up just being a campaigner, because it's the only job I can do, really -- I was campaigning at university, and for the last 10 years, I've been a professional campaigner for large charities, and now I'm a creative campaigner consultant for different charities as well as other work I do -- but I knew that there were other forms of activism that were needed.
I started tinkering about seven years ago to see what quieter forms of activism I could engage with so I didn't burn out as an activist, but also to look at some of the issues I was concerned about in campaigning.
I was very lucky that, when I worked for Oxfam and other big charities, I could read lots of big reports on what influenced politicians and businesses and the general public, what campaigns worked really well, which ones didn't.
And I'm a bit of a geek, so I look at all of that stuff, and I wanted to tinker around to see how I could engage people in social change in a different way, because I think if we want the world to be more beautiful, kind and just, then our activism should be beautiful, kind and just, and often it's not.
And today, I just want to talk about three ways that I think activism needs introverts.
I think there's lot of other ways, but I'm just going to talk about three.
And the first one is: activism is often very quick, and it's about doing, so extroverts, often their immediate response to injustice is, we've got to do stuff now, we've got to react really quickly -- and yes, we do need to react, but we need to be strategic in our campaigning, and if we just act on anger, often we do the wrong things.
I use craft, like needlework -- like this guy behind me is doing -- as a way to not only slow down those extrovert doers, but also to bring in nervous, quiet introverts into activism.
By doing repetitive actions, like handicraft, you can't do it fast, you have to do it slowly.
And those repetitive stitches help you meditate on the big, complex, messy social change issues and figure out what we can do as a citizen, as a consumer, as a constituent, and all of those different things.
It helps you think critically while you're stitching away, and it helps you be more mindful of what are your motives.
Are you that Barbie aid worker that was mentioned before?
Are you about joining people in solidarity, or do you want to be the savior, which often isn't very ethical?
But doing needle work together, as well, extroverts and introverts and ambivert -- everyone's on the scale in different places -- because it's a quiet, slow form of activism, it really helps introverts be heard in other areas, where they are often not heard.
It sounds odd, but while you're stitching, you don't need eye contact with people.
So, for nervous introverts, it means that you can stitch away next to someone or a group of people and ask questions that you're thinking that often you don't get time to ask people, or you're too nervous to ask if you give them eye contact.
So you can get introverts, who are those big, deep thinkers, saying, "That's really interesting that you want to do that extrovert form of activism that's about shaming people or quickly going out somewhere, but who are you trying to target and how, and is that the best way to do it?"
So it means you could have these discussions in a very slow way, which is great for the extrovert to slow down and think deeply, but it's really good for the introvert as well, to be heard and to feel part of that movement for change, in a good way.
Some ways we do it is stitch cards about what values we thread through our activism, and making sure that we don't just react in unethical ways.
One, sometimes we work with art institutions where we will get over 150 people at the V&amp;A who can come for hours, sit and stitch together on a particular issue, and then tweet what they're thinking or how it went, like this one.
Also, I always think that activism needs introverts because we're really good at intimate activism.
So we're good at slow activism, and we're really good at intimate activism, and if this year has told us anything, it's told us that we need to, when we're engaging power holders, we need to engage them by listening to people we disagree with, by building bridges not walls -- walls or wars -- and by being critical friends, not aggressive enemies.
And one example that I do a lot with introverts, but with lots of people, is make gifts for people in power, so not be outside screaming at them, but to give them something like a bespoke handkerchief saying, "Don't blow it.
Use your power for good.
We know you've got a difficult job in your position of power.
How can we help you?"
And what's great is, for the introverts, we can write letters while we're making these gifts, so for us, Marks and Spencer, we tried to campaign to get them to implement the living wage.
So we made all the 14 board members bespoke handkerchiefs.
We wrote them letters, we boxed them up, and we went to the AGM to hand-deliver our gifts and to have that form of intimate activism where we had discussions with them.
And what was brilliant was that the chair of the board told us how amazing our campaign was, how heartfelt it was.
The board members, like Martha Lane Fox, who has hundreds of thousands of followers on Twitter, and highly influential in business, tweeted how impressed she was, and within 10 months, we'd had meetings with Marks and Spencer to say, "We know this is difficult to be a living wage employer, but if you can be one, the rest of the sector will look at it, and it's not right that some of your amazing workers are working full time and still can't pay their bills.
And we love Marks and Spencer.
How can you be the role model that we want you to be?"
So that was that intimate form of activism.
We had lots of meetings with them.
We then gave them Christmas cards and Valentine's cards to say, "We really want to encourage you to implement the living wage, and within 10 months, they'd announced to the media that they were going to pay the independent living wage, and now -- (Applause) Thank you.
And now we're trying to work with them to be accredited, which is really important, and we went back to the last AGM this June and we had these amazing one-to-one discussions with the board members, who told us how much they loved their hankies and how it really moved them, what we were doing, and they all told us that if we were standing outside screaming at them and not being gentle in our protest, they wouldn't have even listened to us, never mind had those discussions with us.
And I think introverts are really good at intimate activism because we like to listen, we like one-to-ones, we don't like small talks, we like those big, juicy issues to discuss with people, we don't like conflict, so we avoid it at all costs, which is really important when we're trying to engage power holders, not to be conflicting with them all the time.
The third way I think activists are really missing out if they don't engage introverts is that introverts, like I said, can be half of the world's population, and most of us won't say that we're introvert, or we get embarrassed by saying what overwhelms us.
So for me, a few years ago, my mom used to send me texts in capital letters -- and she can now do emojis and everything, she's fine -- but as soon as I'd see this text, I'd wince and think, "Ooh, it's capital letters, it's too much."
And I'd have to ignore it to read the lovely text she sent me.
And that's a bit embarrassing, to tell people that capital letters overwhelm you, but we really need introverts to help us do intriguing activism that attracts them rather than puts them off.
We're put off by big and brash giant posters and capital letters and explanation marks telling us what to do and vying for our attention.
So some of the things I do with people around the world who take part is make small bits of provocative street art which are hung off eye level, very small, and they're provocative messages.
They're not preaching at people or telling them what to do.
They're just getting people to engage in different ways, and think for themselves, because we don't like to be told what to do.
It might be wearing a green heart on your sleeve saying what you love and how climate change will affect it, and we'll wear it, and if people say, "Why are you wearing a green heart with the word 'chocolate' on?"
and we can have those one-to-one intimate conversations and say, "I love chocolate.
Climate change is going to affect it, and I think there's lot of other things that climate change will affect, and I really want to make sure I'm part of the solution, not the problem."
And then we deflect, because we don't like to be the center of attention, and say, "What do you love and how will climate change affect it?"
Or it might be shop-dropping instead of shop-lifting, where we'll make little mini-scrolls with lovely stories on about what's the story behind your clothes.
Is it a joyful story of how it's made, or is it a torturous one?
And we'll just drop them in little pockets in shops, all lowercase, all handwritten, with kisses and smiley faces in ribbon, and then people are excited that they found it.
And we often drop them in unethical shops or in front pockets, and it's a way that we can do offline campaigning that engages us and doesn't burn us out, but also engages other people in an intriguing way online and offline.
So I've got two calls to action, for the introverts and for the extroverts.
For the ambivert, you're involved in all of it.
For the extroverts, I want to say that when you're planning a campaign, think about introverts.
Think about how valuable our skills are, just as much as extroverts'.
We're good at slowing down and thinking deeply, and the detail of issues, we're really good at bringing them out.
We're good at intimate activism, so use us in that way.
And we're good at intriguing people by doing strange little things that help create conversations and thought.
Introverts, my call to action for you is, I know you like being on your own, I know you like being in your head, but activism needs you, so sometimes you've got to get out there.
It doesn't mean that you've got to turn into an extrovert and burn out, because that's no use for anyone, but what it does mean is that you should value the skills and the traits that you have that activism needs.
So for everyone in this room, whether you're an extrovert or an introvert or an ambivert, the world needs you now more than ever, and you've got no excuse not to get involved.
Thanks.
(Applause)