Someone knows over here?

Obviously, the answer is "come here bear."

Camembert!

(Laughter)

Camembert!

(Applause)

Thank you.

I have a head full of cheese puns,

but I was told I had to keep it 'brie'-f.

(Laughter)

What did the piece of cheese say

when it looked into the mirror?

No. It said, "Halloumi."

(Laughter)

Hello me!

What can I say guys? I love a good pun.

Why?

I don't know;

because puns are funny, right?

Why?

Well, because there is a bit of a surprise factor.

You feel outsmarted for a second until you get the double meaning.

Why?

Because that's the way language works.

OK. I get what these slides are doing.

They're playing the why game

where you keep asking, "Why, why, but why?"

after everything someone says.

Kids do it all of the time

and adults should do it more often.

I'm just kidding. Don't. It's annoying.

(Laughter)

You can ask why, over, and over, and over again for ever,

even if one day, we explain

every physical interaction, and scientific law,

and hope, and dream, and regret with a single elegant equation.

You could still ask, "Why? Why that equation?

Why doesn't the universe operate with some different equation?"

So, yes; the why game is irritating, it's annoying,

and it's what I do for a living.

Every week, for the past few years,

I have researched a big question, a funny why question.

I've researched the science's, the mathematics’s recent theories

behind all kinds of things.

I do this on my YouTube channel: Vsauce.

So, Vsauce, in the last couple of years, has grown phenomenally.

It's hard to believe.

I'm now doing more than 30 million views every single month,

with five and a half subscribers

growing more than 10,000 new subscribers every day.

It's awesome. I love it.

I get to ask some pretty ridiculous questions.

For instance, "Is anything real?"

Come on! How can you possible answer that?

Well, that's not really the point.

The point is to bring people in with a great question,

make them curious, and once they're there,

accidentally teach them a whole bunch of things about the universe.

(Laughter)

Some examples of other questions I've asked:

how much does a shadow weigh?

What does it mean to ask a question like that, "What us a shadow?"

What color is a mirror?

In answering this question, you could explain a lot

about specular reflection, the physics of light.

This is one of my favorites, "Why are things creepy?

(Laughter)

I often go into psychology - that's more where my background is in -

but a question I have yet to answer, - hopefully, someone out there knows -

please tell me why is this called your 'bottom'

if it's technically in the middle of your body?

(Laughter)

It's ridiculous.

But it's a really good question.

I ask questions all of the time, but today, this is my question.

Why do we ask questions?

Seriously. I mean, what's the point?

Who cares why things are creepy? They just are.

Who cares why this is called my bottom?

It's gross, don't do that anymore.

Questions.

How do I get people to care about these questions?

Especially people who think that learning is boring.

I like to believe that the limits of what you can be interested in

are unlimited.

And this is my story.

I began making YouTube videos about six years ago,

but only recently did I start making explanatory videos.

I've no idea what took me so long.

I have been explaining things my entire life.

Except, usually, I did it alone, out loud.

I talk to myself when I'm alone; all the time.

If you snuck up on me when I didn't think anyone was around,

you would overhear me explaining the most mundane stuff.

It's kind of weird, maybe.

OK, it's really weird, but for me, it is a great way,

for me to know that I kind of know more what I'm talking about

if I can verbally explain it.

As Albert Einstein said,

"If you can't explain it simply, you don't understand it well enough."

When I was a teenager, I discovered a competitive speaking program

and one of the events was informative speaking,

where you literally got to write a speech explaining something to judges,

and then you were given points and medals if you were good enough.

My very first informative speech ever was about ketchup:

the history of ketchup. the etymology of the name,

its legal status, the physics of its viscosity, and how it flowed.

It was super nerdy stuff.

But at my very, very first public speaking tournament

I took first place.

Hey!

(Applause)

Look at that guy.

(Applause)

Some of the hair here moved down here, but other than that,

I'm the same guy.

Seriously, I'm still doing the same thing.

To be at that tournament and to see the expression on someone's face

when they suddenly understand and are fascinated by something,

in the same way that you are

is a phenomenal feeling.

I've learned two things from this:

first of all, people love a good explanation.

They hunt them down.

Even people who say they hate learning, and hate books, and all that stuff,

pff, they love explanations.

Second of all, if you look closely enough

and you take the time,

anything can be interesting to anyone

because everything is related in some way to something they care about.

Richard Feynman called

"the pleasure of finding things out" a "kick in the discovery."

And I agree, but I think there might be a little bit more to that.

Let's get rid of this picture of me.

We want to express ourselves,

everyone wants to express themselves.

They do it through the music they listen to, the clothing they wear,

the way they act, but they also do it with knowledge.

The things they know about the stuff they like,

Their interests, their hobbies.

I've noticed that the most operative motive

behind someone sharing one of my videos, promoting me by word of mouth,

isn't so much about me as it is about them.

"Hey! Look what I found!", "I like this."

"I am like this."

Whenever you share a video, whenever you share anything,

a few of the attributes of that thing reflect back onto you.

I've found that one of the best ways to gain attentive listeners

is not to be who you think your audience wants you to be,

but instead, to say, and make, and show things

that allow your audience or your students to be who they want to be.

I once discussed in a video,

"Why the sky is blue?"

And backstage, when I was going through what I want to to talk about,

I ran into this girl.

This seriously actually happened backstage, go find her.

I said, "Do you know why the sky is blue?"

She said, "I think I used to know, but it didn't really mattered."

Exactly. Exactly.

And I knew that was going to be a problem.

It turns out that the sky is blue

because of the way light scatters in our atmosphere.

It's called Rayleigh scattering.

A light of shorter wave lengths scatters more,

so, greens, blues, and violets.

That's why when you look at the sky away from the Sun,

you see this beautiful sky blue;

it's all of those shorter wave lengths combining.

When you look directly at the Sun - which you shouldn't do very often;

don't do it ever -

you see the longer wave lengths which are surviving that scattering.

That's why the Sun looks yellow during the day.

Of course, when the Sun's light needs to travel through a whole lot of air

to get into your eyeball,

a lot of scattering occurs,

and only really, really long wave lengths make it all the way there

directly from the Sun,

which is why it looks orange, or sometimes red at sunrise or sunset.

I think that's really cool, but obviously, some people

- including someone backstage right now -, don't.

Or maybe they already know it,

or could probably figure out if they thought about it.

So what do you do?

I'm trying to collect the largest audience possible that I can,

I want to appeal to and attract as many people as possible.

So what I do is I camp out with the subject.

In this case, Rayleigh scattering.

I've learned as much about it as I can.

What else is it responsible for?

Who is it named after? Who did he love?

Whatever I can find that could become a great hook

to bring in just the right person.

So, in this case, I've read about Rayleigh scattering,

and I realized-- I didn't realize, I learned,

that blue eyes are blue for the exact same reason.

Blue eyes do not have blue pigment in them.

Ouch! That would hurt if that was real.

Blue eyes don't have blue pigment in them

any more than the air has blue pigment in it.

If you were to rip out my iris, I would be like, "Ouch!" but then

(Laughter)

if you grounded it up into a fine powder, it wouldn't be blue anymore

it would be a dull brownish-blackish color.

Instead, blue eyes are blue because at a microscopic level,

their texture scatters light

just like the air in our atmosphere scatters the Sun's light

to make the sky blue.

Maybe you already know why the sky is blue,

maybe you don't care,

but maybe you will be fascinated by something like this.

This is why my episodes often seem to go all over the place.

It's not just because I'm crazy it's also because I want to have

as many hooks out as possible

to catch as many people and to make them interested.

I once did a video about rainbows.

I thought, "Some people might think rainbows are lame."

I'll teach about rainbows.

What other types of bows are there?

Well, like when a string, like a knot...

Is a bow a knot?

Why do headphones always get tied up into knots?

I researched the mathematics behind this; it's fascinating.

([Laughter)

I'll spare you all of the details;

also, this will allow you to go check out my videos

and give me many, many views rather than just one.

In the 1950s, Harold Edgerton took a series of amazing pictures

of nuclear explosions.

This is a detonation

just milliseconds after happening,

with an exposure time of one billionth of a second.

You can see the energy of this plasma ball,

the energy of the explosion is vaporizing the metal wires holding up the tower.

That's where these glowing, spindly legs come form.

His work attracted wider and new interest to physical phenomenon

simply because he featured something

that people couldn't help but want to look at.

A moment you couldn't witness alone.

He famously said, "The trick to education

is to teach in such a way

that people only find out they're learning when it's too late."

(Laughter)

It works for me.

So recently, I took on the most difficult question ever,

but also the most requested,