This is Caitlin from SciShow Space and sometimes SciShow.
This is Jessi from Animal Wonders Montana.
This is Hank Green, who you may know from SciShow and Crash
Course and VlogBrothers.
Are there any other places we should know you're from?
That's a good start.
This is where Hank is from.
So first question for you, Jessi.
Yeah.
A bat and a ball cost $1.10.
OK.
The bat costs $1 more than the ball.
How much is the ball?
The bat costs $1 more than the ball.
This is like flashbacks to the SATs.
I hate this so much.
$1.
Wait.
The bat costs $1 more than the ball.
Yes.
The bat costs $1 more than the ball.
How much is the ball?
$0.10 Am I wrong?
You're not wrong, except there's another answer.
That's right.
That's better.
That's more accurate.
So the bat is $1.05.
How much is the ball?
$0.05.
Yes.
Most people are with you.
And to be honest, the question is designed for you
to give that answer.
Yes.
The question wants you to say that.
Uh-huh.
Which is I knew I was wrong.
Yes?
Yes.
Yes!
I was going to say $1.05, but then I was like wait,
isn't the ball $1?
So--
Yeah.
But you corrected yourself like immediately
as you were talking.
But there are more questions.
And now, you may stop and reflect
on what you should be saying.
OK.
I don't want this to cause you deep emotional anguish.
Question number two.
OK.
If 5 machines take 5 minutes to make 5 widgets,
how long do 100 machines take to make 100 widgets?
100 minutes.
My very first instinct was to say 20 minutes.
Oh, interesting.
My heart is beating so fast.
Oh no!
OK.
So we have 5 machines taking 5 minutes to make 5 widgets.
And then we just up-- we up the machines and we up the output.
So we upped the machines to 100.
We have an output of 100.
But--
5 minutes.
Yes.
Because you have 5 machines making 5 widgets.
Yeah.
So then you have 100 machines.
You don't have 5 making 100 things.
Yeah.
Yes.
That makes perfect sense.
It does when you think about it.
But the thing is with this test, it's
not designed to allow you to think about it, right?
It wants you to give this really quick answer.
Right.
That is two from two for Caitlin.
Caitlin is doing a great job.
How many questions are there?
I'm nervous.
Oh.
Brain.
In a lake, there's a patch of lily pads
that doubles in size every day.
Yeah?
It takes the patch 48 days to cover the entire lake.
How long does it take for the patch
to cover half of the lake?
I've heard this one before.
Wait.
And it takes how many days to fill up the whole lake?
It takes 48 days for the patch to fill up the entire lake,
so how many days does it take for it fill up
half of the lake?
So 47 days?
Yes.
Um, 47 days?
So 47 days.
Yes.
Yeah.
Hey, I got one right!
Yay!
But I've heard that one before, so I kind of cheated.
You didn't cheat.
You thought about it correctly.
OK.
Yeah.
I didn't have my immediate response.
So this test is called the Cognitive Reflection Test.
And it was developed by American psychologist Shane Frederick
and it was first published in 2005.
He first gave this test in over like 35 different scenarios
to over 3,000 people.
The point of the test and why it's named
this is that it causes you or it wants
you to cognitively reflect.
And 33% of the people, or 1/3 of the people,
missed all of the questions.
So you have different systems of processing
in your brain, which you've probably heard about before.
There's a theory called Dual Processing Theory which talks
about System 1 and System 2.
System 1 is like your gut response to something.
It's often referred to as your intuition.
And it's very fast and quick.
And that is the system that wants
you to go, oh, of course it costs $1,
rather than saying $1.05.
And System 2 is a more slow--
Wait a second.
---considered and logical way of thinking that we don't always
do, but we have to kind of step back and look at it
differently.
It's been called thinking fast and thinking slow.
When he gave the questions to students at MIT, only 48%
of the students could answer all of the questions correctly.
At Princeton, only 26% of the students
could answer all of the questions correctly.
Yeah.
It's difficult.
Well, don't give-- don't try and make any excuses for me.
I think it's tough.
When I first did it, I got the lily pads one correct.
I got the bat and the ball wrong.
So we're going to move on to the second test.
And this is another riddle.
OK.
A father and son are in a horrible car accident.
Yes.
The father dies at the scene and the son
is rushed to hospital.
Uh-huh.
When the son is being prepped for surgery,
the surgeon comes in and says, gosh, I
can't perform this operation.
This is my son.
Who is the surgeon?
What do you mean?
Who is the surgeon?
Wait.
OK.
The father and the son are in an accident.
The father dies at the scene.
So his father's dead.
His father's dead.
The son is rushed to hospital.
Son's being prepped for surgery.
The surgeon walks in and says, oh my gosh.
I can't do this.
This is my son.
Who is the surgeon?
I mean, I have in the space of looking
at you come up with several different scenarios.
Let's talk through them.
Let's talk through all the scenarios.
All right.
Well, there are many-- there are many different ways
in which you can have more than one father.
Yes.
You could have a gay couple that is your parents.
Yes.
You could have an adopted father and a biological father.
Yes.
You could have a stepfather.
Uh-huh.
You can have many different stepfathers.
Uh-huh.
The grandpa?
You can have a priest who is your father.
Like my father, like he was in a car with the priest--
Yes.
---that was in charge of his church.
Yes.
That father.
Yes.
And then his actual father is--
Yes.
But that doesn't make sense.
Is this anywhere where we're headed in the right direction?
It's one direction.
It may not be the right way that I
want to drive in my little answer car.
But-- and like it's a logic problem, so I'm like oh,
it's-- oh, it's his mother.
OK.
You can also have two different parents.
Oh.
Yes.
His mom.
HANK GREEN: Oh, god.
I'm leaving.
Bye, Hank.
[LAUGHTER]
That wasn't that hard.
Yeah.
While Hank's gone, I just want to say
that when I first did this, I thought I was so clever
and I said, obviously, the boy has two dads.
That was my response.
HANK GREEN: OK.
OK.
The question is set up--
And this test has been done on both men and women
and men and women equally have the same response
where people don't think that the mother is the surgeon.
It's not just the bias that we think it's a doctor,
it must be a man.
Uh-huh.
It is also the fact that you have set it
up like this is a quandary, how do you
solve this bizarre quandary?
Yes.
And so you're looking for a problem.
Yes.
And looking to solve the problem.
Well, and it's interesting too because you're
using all-- like all the pronouns you're using are male.
Yes.
And so I wonder--
It's designed to trick you.
Like, yeah.
But I wonder what would happen if it was a different like-- I
guess, if it was like our biases about like if the nurse came
in, I'd be like, oh, it's his mother.
But it's also the bias.
Yes.
Hank left the room.
I got hung up on it.
But it gets easier to consider these when you know
that I'm trying to trick you.
There's a trick.
There's a trick, exactly.
Yeah.
There's another test with kids that you
may have seen that kind of tests assumptions and things
like that.
It's called the Draw-a-Person Test.
So kids are often asked, like, draw what a scientist looks
like, or something like that.
Right.
Yeah.
And they kind of-- we'll see that the kids will more often
draw a man who's in a lab coat in a lab
or something like that, where scientists
work in all different environments
and can be all different people.
Uh, yeah.
It's almost a riddle.
But I stand by everything I said and I'm not
going to say anything else.
So I guess these questions kind of challenge the assumptions
that we have about people when we're not
given the full information.
Anyway, I'll let you go.
Those were good.
Thank you so much for asking me hard questions.
You're welcome.
Thank you.
Thank you so much.
Yeah.
Thank you.
Hank, thank you so much for being on BrainCraft.
Yes.
Thank you for humiliating me.
You're welcome.