humor, comedy. What makes something

funny and when something's funny, why do we laugh?

What's the purpose of laughing and why do we laugh when we're tickled?

Well, people study this. They're called gelotologists

and we don't have all the answers yet, but what we do know is that you are

thirty times more likely to laugh

if there are other people around.

We also know that babies laugh before they learn a language

and that babies born blind and deaf will laugh.

There are thousands of languages, hundreds of thousands of dialects, but yet we

all

laugh in much the same way. Our brains are constantly looking for

patterns - ways of understanding the world and predicting what's next. It's to our

evolutionary advantage. And so when something begins in a way that we expect

and then all of a sudden changes and surprises or delights us,

we often react with laughter, because we have just

learned something. We've learned a new

logical order. This theory posits that things are

funny because there's an incongruity between what we expected

and what happened. Whether it's a dog

dressed like a human or a clever use of word play.

In other words, comedy is about learning.

But once you've learned the new logical order of the joke,

well it ceases to be funny, which is why jokes are funny the first time,

but not every other time after that. Take a look at this

percentage sign. Alright, so you know what a percent sign is.

But besides the percent, there's also a permil

and permyriad symbol. But that's not

funny, because even though it might be new information to you, it still falls

right in line with the logic of the percent symbol. But what Demetri Martin shows

us

with just one more line, you can make it look like a man cheering

after taking a dump... well, that surprises us.

But we don't only laugh when something's funny.

What about tickling? How does that make any sense? Most of us don't like being

tickled, but when tickled we can't help but smile

and laugh. Well, a possible explanation is that tickling

helps teach children at a young age proper defensive

behaviors. Is it a coincidence that the most ticklish areas are also

the most vulnerable and the ones that we instinctively cover

when startled. Also, because being tickled makes the person laugh,

it may encourage others to tickle them, teaching them

these defensive skills. Tickling may even play a role

before you are born. In order to avoid being tickled, a baby

gets into a better position to be delivered.

Now, physically, laughing involves the

epiglottis - a little flap thing that protects the trachea

whenever we swallow, so that food and water doesn't go down into our lungs.

I know it doesn't look very funny,

but this is where the laugh happens. The epiglottis constricts the larynx

and we get the LOL. Interestingly,

the epiglottis actually has taste buds on it, which means that,

anatomically speaking, comedy truly is

a matter of taste.

Get out of my house!

And as always,

thanks for watching.