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TEDxUppsalaUniversity

Petter Johansson: Do you really know why you do what you do?

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Experimental psychologist Petter Johansson researches choice blindness -- a phenomenon where we convince ourselves that we're getting what we want, even when we're not. In an eye-opening talk, he shares experiments (designed in collaboration with magicians!) that aim to answer the question: Why do we do what we do? The findings have big implications for the nature of self-knowledge and how we react in the face of manipulation. You may not know yourself as well as you think you do.

- Experimental psychologist
Petter Johansson and his research group study self-knowledge and attitude change using methods ranging from questionnaires to close-up card magic. Full bio

So why do you think
the rich should pay more in taxes?
00:12
Why did you buy the latest iPhone?
00:16
Why did you pick your current partner?
00:18
And why did so many people
vote for Donald Trump?
00:21
What were the reasons, why did they do it?
00:24
So we ask this kind
of question all the time,
00:27
and we expect to get an answer.
00:30
And when being asked,
we expect ourselves to know the answer,
00:31
to simply tell why we did as we did.
00:35
But do we really know why?
00:38
So when you say that you prefer
George Clooney to Tom Hanks,
00:41
due to his concern for the environment,
00:44
is that really true?
00:46
So you can be perfectly sincere
and genuinely believe
00:48
that this is the reason
that drives your choice,
00:51
but to me, it may still feel
like something is missing.
00:54
As it stands, due to
the nature of subjectivity,
00:57
it is actually very hard to ever prove
that people are wrong about themselves.
01:00
So I'm an experimental psychologist,
01:06
and this is the problem
we've been trying to solve in our lab.
01:08
So we wanted to create an experiment
01:12
that would allow us to challenge
what people say about themselves,
01:14
regardless of how certain they may seem.
01:18
But tricking people
about their own mind is hard.
01:21
So we turned to the professionals.
01:24
The magicians.
01:27
So they're experts at creating
the illusion of a free choice.
01:29
So when they say, "Pick a card, any card,"
01:32
the only thing you know
is that your choice is no longer free.
01:34
So we had a few fantastic
brainstorming sessions
01:38
with a group of Swedish magicians,
01:40
and they helped us create a method
01:42
in which we would be able to manipulate
the outcome of people's choices.
01:44
This way we would know
when people are wrong about themselves,
01:48
even if they don't know this themselves.
01:51
So I will now show you
a short movie showing this manipulation.
01:54
So it's quite simple.
01:59
The participants make a choice,
02:00
but I end up giving them the opposite.
02:02
And then we want to see:
How did they react, and what did they say?
02:05
So it's quite simple, but see
if you can spot the magic going on.
02:09
And this was shot with real participants,
they don't know what's going on.
02:13
(Video) Petter Johansson:
Hi, my name's Petter.
02:19
Woman: Hi, I'm Becka.
02:21
PJ: I'm going to show you
pictures like this.
02:22
And you'll have to decide
which one you find more attractive.
02:24
Becka: OK.
02:27
PJ: And then sometimes,
I will ask you why you prefer that face.
02:28
Becka: OK.
02:32
PJ: Ready?
Becka: Yeah.
02:33
PJ: Why did you prefer that one?
02:43
Becka: The smile, I think.
02:44
PJ: Smile.
02:46
Man: One on the left.
02:52
Again, this one just struck me.
02:57
Interesting shot.
02:59
Since I'm a photographer,
I like the way it's lit and looks.
03:01
Petter Johansson: But now comes the trick.
03:06
(Video) Woman 1: This one.
03:10
PJ: So they get the opposite
of their choice.
03:16
And let's see what happens.
03:20
Woman 2: Um ...
03:28
I think he seems a little more
innocent than the other guy.
03:35
Man: The one on the left.
03:45
I like her smile
and contour of the nose and face.
03:49
So it's a little more interesting
to me, and her haircut.
03:53
Woman 3: This one.
04:00
I like the smirky look better.
04:03
PJ: You like the smirky look better?
04:05
(Laughter)
04:09
Woman 3: This one.
04:12
PJ: What made you choose him?
04:15
Woman 3: I don't know,
he looks a little bit like the Hobbit.
04:17
(Laughter)
04:20
PJ: And what happens in the end
04:22
when I tell them the true nature
of the experiment?
04:24
Yeah, that's it. I just have to
ask a few questions.
04:27
Man: Sure.
04:29
PJ: What did you think
of this experiment, was it easy or hard?
04:30
Man: It was easy.
04:33
PJ: During the experiments,
04:36
I actually switched
the pictures three times.
04:37
Was this anything you noticed?
04:40
Man: No. I didn't notice any of that.
04:42
PJ: Not at all?
Man: No.
04:44
Switching the pictures as far as ...
04:45
PJ: Yeah, you were pointing at one of them
but I actually gave you the opposite.
04:47
Man: The opposite one.
OK, when you --
04:51
No. Shows you how much
my attention span was.
04:53
(Laughter)
04:55
PJ: Did you notice that sometimes
during the experiment
04:58
I switched the pictures?
05:01
Woman 2: No, I did not notice that.
05:04
PJ: You were pointing at one,
but then I gave you the other one.
05:06
No inclination of that happening?
05:09
Woman 2: No.
05:11
Woman 2: I did not notice.
05:13
(Laughs)
05:14
PJ: Thank you.
05:16
Woman 2: Thank you.
05:17
PJ: OK, so as you probably
figured out now,
05:19
the trick is that I have
two cards in each hand,
05:21
and when I hand one of them over,
05:23
the black one kind of disappears
into the black surface on the table.
05:25
So using pictures like this,
05:30
normally not more than 20 percent
of the participants detect these tries.
05:32
And as you saw in the movie,
05:36
when in the end
we explain what's going on,
05:38
they're very surprised and often refuse
to believe the trick has been made.
05:41
So this shows that this effect
is quite robust and a genuine effect.
05:45
But if you're interested
in self-knowledge, as I am,
05:50
the more interesting bit is,
05:53
OK, so what did they say
when they explained these choices?
05:54
So we've done a lot of analysis
05:58
of the verbal reports
in these experiments.
06:00
And this graph simply shows
06:03
that if you compare
what they say in a manipulated trial
06:05
with a nonmanipulated trial,
06:10
that is when they explain
a normal choice they've made
06:12
and one where we manipulated the outcome,
06:14
we find that they are remarkably similar.
06:17
So they are just as emotional,
just as specific,
06:19
and they are expressed
with the same level of certainty.
06:22
So the strong conclusion to draw from this
06:27
is that if there are no differences
06:29
between a real choice
and a manipulated choice,
06:31
perhaps we make things up all the time.
06:35
But we've also done studies
06:38
where we try to match what they say
with the actual faces.
06:40
And then we find things like this.
06:43
So here, this male participant,
he preferred the girl to the left,
06:45
he ended up with the one to the right.
06:50
And then, he explained
his choice like this.
06:52
"She is radiant.
06:55
I would rather have approached her
at the bar than the other one.
06:56
And I like earrings."
07:00
And whatever made him choose
the girl on the left to begin with,
07:01
it can't have been the earrings,
07:05
because they were actually
sitting on the girl on the right.
07:06
So this is a clear example
of a post hoc construction.
07:09
So they just explained
the choice afterwards.
07:13
So what this experiment shows is,
07:17
OK, so if we fail to detect
that our choices have been changed,
07:19
we will immediately start
to explain them in another way.
07:23
And what we also found
07:27
is that the participants
often come to prefer the alternative,
07:28
that they were led to believe they liked.
07:32
So if we let them do the choice again,
07:34
they will now choose the face
they had previously rejected.
07:36
So this is the effect
we call "choice blindness."
07:41
And we've done
a number of different studies --
07:43
we've tried consumer choices,
07:46
choices based on taste and smell
and even reasoning problems.
07:48
But what you all want to know is of course
07:53
does this extend also
to more complex, more meaningful choices?
07:55
Like those concerning
moral and political issues.
07:59
So the next experiment,
it needs a little bit of a background.
08:04
So in Sweden, the political landscape
08:08
is dominated by a left-wing
and a right-wing coalition.
08:12
And the voters may move a little bit
between the parties within each coalition,
08:17
but there is very little movement
between the coalitions.
08:22
And before each elections,
08:25
the newspapers and the polling institutes
08:27
put together what they call
"an election compass"
08:31
which consists of a number
of dividing issues
08:34
that sort of separates the two coalitions.
08:37
Things like if tax on gasoline
should be increased
08:40
or if the 13 months of paid parental leave
08:44
should be split equally
between the two parents
08:48
in order to increase gender equality.
08:50
So, before the last Swedish election,
08:54
we created an election compass of our own.
08:57
So we walked up to people in the street
09:00
and asked if they wanted
to do a quick political survey.
09:02
So first we had them state
their voting intention
09:06
between the two coalitions.
09:08
Then we asked them
to answer 12 of these questions.
09:10
They would fill in their answers,
09:14
and we would ask them to discuss,
09:16
so OK, why do you think
tax on gas should be increased?
09:18
And we'd go through the questions.
09:23
Then we had a color coded template
09:25
that would allow us
to tally their overall score.
09:29
So this person would have
one, two, three, four
09:32
five, six, seven, eight, nine
scores to the left,
09:36
so he would lean to the left, basically.
09:39
And in the end, we also had them
fill in their voting intention once more.
09:42
But of course, there was
also a trick involved.
09:48
So first, we walked up to people,
09:51
we asked them
about their voting intention
09:53
and then when they started filling in,
09:55
we would fill in a set of answers
going in the opposite direction.
09:57
We would put it under the notepad.
10:03
And when we get the questionnaire,
10:06
we would simply glue it on top
of the participant's own answer.
10:08
So there, it's gone.
10:16
And then we would ask
about each of the questions:
10:24
How did you reason here?
10:26
And they'll state the reasons,
10:28
together we will sum up
their overall score.
10:30
And in the end, they will state
their voting intention again.
10:34
So what we find first of all here,
10:41
is that very few of these
manipulations are detected.
10:43
And they're not detected
in the sense that they realize,
10:47
"OK, you must have changed my answer,"
10:50
it was more the case that,
10:52
"OK, I must've misunderstood
the question the first time I read it.
10:53
Can I please change it?"
10:56
And even if a few of these
manipulations were changed,
10:59
the overall majority was missed.
11:04
So we managed to switch 90 percent
of the participants' answers
11:06
from left to right, right to left,
their overall profile.
11:10
And what happens then when
they are asked to motivate their choices?
11:14
And here we find much more
interesting verbal reports
11:20
than compared to the faces.
11:23
People say things like this,
and I'll read it to you.
11:25
So, "Large-scale governmental surveillance
of email and internet traffic
11:29
ought to be permissible as means to combat
international crime and terrorism."
11:33
"So you agree to some extent
with this statement." "Yes."
11:37
"So how did you reason here?"
11:40
"Well, like, as it is so hard to get
at international crime and terrorism,
11:43
I think there should be
those kinds of tools."
11:48
And then the person remembers an argument
from the newspaper in the morning.
11:51
"Like in the newspaper today,
11:55
it said they can like,
listen to mobile phones from prison,
11:56
if a gang leader tries to continue
his crimes from inside.
12:00
And I think it's madness
that we have so little power
12:03
that we can't stop those things
12:06
when we actually have
the possibility to do so."
12:08
And then there's a little bit
back and forth in the end:
12:11
"I don't like that they have access
to everything I do,
12:13
but I still think
it's worth it in the long run."
12:16
So, if you didn't know that this person
12:19
just took part in
a choice blindness experiment,
12:21
I don't think you would question
12:23
that this is the true attitude
of that person.
12:25
And what happens in the end,
with the voting intention?
12:29
What we find -- that one is also
clearly affected by the questionnaire.
12:32
So we have 10 participants
12:37
shifting from left to right
or from right to left.
12:39
We have another 19
that go from clear voting intention
12:42
to being uncertain.
12:44
Some go from being uncertain
to clear voting intention.
12:46
And then there is a number of participants
staying uncertain throughout.
12:49
And that number is interesting
12:54
because if you look
at what the polling institutes say
12:55
the closer you get to an election,
13:00
the only people that are sort of in play
13:02
are the ones that are
considered uncertain.
13:04
But we show there is a much larger number
13:06
that would actually consider
shifting their attitudes.
13:10
And here I must point out, of course,
that you are not allowed to use this
13:13
as an actual method
to change people's votes
13:17
before an election,
13:19
and we clearly debriefed them afterwards
13:21
and gave them every
opportunity to change back
13:24
to whatever they thought first.
13:27
But what this shows is
that if you can get people
13:30
to see the opposite view and engage
in a conversation with themselves,
13:32
that could actually make them
change their views.
13:38
OK.
13:42
So what does it all mean?
13:44
What do I think is going on here?
13:46
So first of all,
13:48
a lot of what we call self-knowledge
is actually self-interpretation.
13:50
So I see myself make a choice,
13:55
and then when I'm asked why,
13:57
I just try to make
as much sense of it as possible
14:00
when I make an explanation.
14:02
But we do this so quickly
and with such ease
14:04
that we think we actually know the answer
when we answer why.
14:07
And as it is an interpretation,
14:13
of course we sometimes make mistakes.
14:16
The same way we make mistakes
when we try to understand other people.
14:18
So beware when you ask people
the question "why"
14:23
because what may happen
is that, if you asked them,
14:26
"So why do you support this issue?"
14:31
"Why do you stay in this job
or this relationship?" --
14:35
what may happen when you ask why
is that you actually create an attitude
14:39
that wasn't there
before you asked the question.
14:42
And this is of course important
in your professional life, as well,
14:45
or it could be.
14:48
If, say, you design something
and then you ask people,
14:49
"Why do you think this is good or bad?"
14:52
Or if you're a journalist
asking a politician,
14:54
"So, why did you make this decision?"
14:57
Or if indeed you are a politician
15:00
and try to explain
why a certain decision was made.
15:02
So this may all seem a bit disturbing.
15:06
But if you want to look at it
from a positive direction,
15:09
it could be seen as showing,
15:13
OK, so we're actually
a little bit more flexible than we think.
15:14
We can change our minds.
15:18
Our attitudes are not set in stone.
15:20
And we can also change
the minds of others,
15:22
if we can only get them
to engage with the issue
15:25
and see it from the opposite view.
15:28
And in my own personal life,
since starting with this research --
15:31
So my partner and I,
we've always had the rule
15:35
that you're allowed to take things back.
15:37
Just because I said
I liked something a year ago,
15:40
doesn't mean I have to like it still.
15:42
And getting rid of the need
to stay consistent
15:45
is actually a huge relief and makes
relational life so mush easier to live.
15:48
Anyway, so the conclusion must be:
15:53
know that you don't know yourself.
15:57
Or at least not as well
as you think you do.
15:59
Thanks.
16:03
(Applause)
16:04

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About the speaker:

Petter Johansson - Experimental psychologist
Petter Johansson and his research group study self-knowledge and attitude change using methods ranging from questionnaires to close-up card magic.

Why you should listen

Petter Johansson is an associate professor in cognitive science, and together with Lars Hall he runs the Choice Blindness Lab at Lund University in Sweden. 
 
The main theme of Johansson's research is self-knowledge: How much do we know about ourselves, and how do we come to acquire this knowledge? To study these questions, he and his collaborators have developed an experimental paradigm known as "choice blindness." The methodological twist in these experiments is to use magic tricks to manipulate the outcome of people's choices -- and then measure to what extent and in what ways people react to these changes. The general finding is that participants often fail to detect when they receive the opposite of their choice, and when asked to explain, they readily construct and confabulate answers motivating a choice they only believe they intended to make. The effect has been demonstrated in choice experiments on topics such as facial attractiveness, consumer choice and moral and political decision making.

More profile about the speaker
Petter Johansson | Speaker | TED.com