Secrets of the mind and free will -- revealed by magic tricks

Are you in control of your choices? Magic tricks might reveal otherwise, says scientist and illusionist Alice Pailhès. Watch closely as she performs magic tricks that unveil how your brain works, how you can be subtly influenced and what that means for free will and your day-to-day life. Did she guess your card right?

Alright.

I'd like to start
with a small imagination exercise.

Imagine you're sitting at this table,
facing me right now.

Now, I'm going to ask you
to push one of these cards towards me.

So please imagine yourself
pushing one of these cards towards me.

OK, so take the number
matching the card you pushed

and remember it --
it's important for later.

Now, I'm going to flip
through this deck of cards

and ask you to choose a card
that you will see in the deck.

Are you ready?

Alright, now that you have
your card in mind,

add the value of your card
to your previous number.

For example, if you chose
the six of clubs, add six,

if it's an ace, add one,

and take 11 for any picture cards.

Have you got your final number in mind?

Perfect.

So please take the item
matching your final number.

Now, here's what's funny.

There are going to be
a lot of people watching this video,

and you all have different quirks
with different preferences.

And yet,

the vast majority of you right now
is thinking about a kiwi,

or, if you're left-handed,
probably a corn on the cob.

Yes, I just tricked you.

And I used your psychological biases

to influence both of your decisions.

I work in the MAGIC Lab

at Goldsmiths University of London,

which is not only a place
where we make assistants vanish,

but where we use magic tricks
to study psychological processes,

such as attention, perception,
deception and free will.

I am fascinated by the subtle factors
that influence our choices,

and how understanding our flaws
can give us back some power.

Magic tricks provide a powerful tool
to investigate this,

and our experiments have shown that.

First, we humans tend to go
for the easiest decisions.

With the card trick I did,

most people tend to choose
the card that I want them to choose,

because I'm presenting it
a bit longer than the others.

And it becomes the easiest
option for your brain.

In our case,

the majority of you probably chose
the ten of hearts, right?

And a lot of other tricks
are based on this principle

of easy decision.

Because magicians are very aware

that our brain, not to say "we,"
tends to be a bit lazy.

The exercise we did with the four cards
is also a good example of this.

It's based on another trick
I investigated,

where I ask participants
to physically push

one of the four cards towards me.

We found that around 60 percent of people
choose the third card from the left,

and if they were left-handed,

they typically chose
the second card from the left.

This is based on the easy-option
principle again,

because the card that most people choose

is the most easy to reach
by the dominant hand.

So, I knew that most of you

would end up with one
of these two numbers,

and this allowed me to estimate

the two most probable things
you would end up with.

But this is not just about magic.

It's also about how we are influenced
in our day-to-day lives.

You know, stories and politicians

play with your mind as well, all the time,

because they also know
that we tend to choose and like

what's easily grabbed or seen.

For instance, when you are in a store,

choosing a bottle of wine or a bag of rice

among many lined up on vertical shelves,

your first instinct is to look

only at the ones that are on the shelves
in front of your eyes, right?

It's easier and requires less effort.

Did you know that many brands
actually negotiate

to be at eye-level
on grocery store shelves

because of that easy-option principle?

And this is a tactic
that many politicians use.

When information is right in front
of our eyes on social media,

it's easily accessible,

and it absolutely affects
our voting behaviors.

Political outcomes,
such as the Brexit referendum

or the American election in 2016,

were heavily influenced
by targeted advertising,

making some information,

which was not necessarily truthful,

disproportionately easily accessible
and visible to specific audiences

to influence their votes.

But here is the good news.

Some simple factors have an impact
on how influencible we are.

In an experiment using the trick
with the four cards,

we found that explicitly
informing participants

that they have a choice

can actually lead them to make
more deliberate decisions,

as opposed to behaving in the way
we are trying to make them behave.

In other words,

I either simply asked participants
to push one of the cards,

or I said,

"Choose a card, and then push it."

And when asked to choose a card,

the percentage of people who impulsively
chose the most reachable one

dropped from 60 to 35 percent.

So, it seems that when we are reminded
that we have control over our choices,

and know that our actions matter,

as opposed to acting without thinking,

we can actually make
more personal decisions

and are less easily influenced.

Let me show you another trick,

invented by a British
mentalist Derren Brown,

to make my point.

This one uses what's called
"priming" in psychology.

Priming happens when exposure to something

influences your thoughts
and behavior later on,

without you being aware

that the first thing
is guiding you to a certain extent.

The trick is usually done
in a more intimate context,

where I would be directly facing you,

but we'll give it a try together.

Just focus on me as best as you can,

but do not let me influence your choice.

I'm going to try and mentally transmit
the identity of a playing card

I'm thinking of.

Are you ready?

OK, so first make the color
bright and vivid.

Imagine a screen in your mind,

and on the screen, the little numbers,
low down in the corners of the cards,

and then in the top of the cards.

And then the things in the middle,

in the center of the cards,

the boom, boom, boom, the suits.

Did you get it?

OK, so I'm going to bet
that the majority of you

thought about the three of diamonds,

but chose another card, right?

As you might have noticed,

I heavily tried to influence
your choice with my gestures

while giving you the instructions.

By studying this trick,

we found that around 18 percent of people
choose the three of diamonds,

and nearly 40 percent choose
the three of any suit,

while being completely oblivious
of the fact I was manipulating them.

So what happened here?

Because you were aware

that I was trying
to influence your choice,

you probably paid more attention
to what I was doing.

And this led the majority of you
to choose more consciously

than our participants
who have no information

about who I am, what I'm studying

or what I'm trying to do with their minds.

So the thing is,

in all of our experiments,

we managed to heavily influence
people's card choices,

while they report feeling completely free
and in control of their choice.

And this lack of self-awareness

makes politicians, companies

and other people's influence
all the more powerful,

because we might think we are in control
of our choice and beliefs

when we are not.

Politically or in our consumer behaviors,

if we don't pay attention,

misleading content or showy ads
can just trick our mind.

What if, in our day-to-day lives,

we would stop more often
and consciously choose

before acting on this impulsive,
reactive beast inside of us?

We can actually act more consciously

if we keep in mind

that we have the capacity
to be influenced.

Thank you.