[Music]
so a few weeks ago my boyfriend Igor and
I we were hanging out on the sofa and he
turns to me and says Nev
what do you think the likelihood is that
so naturally we both took a pen and
paper and wrote down our three-year
predictions and through in our 1 year
and 10 year ones for good measure and
these are the results fortunately we are
pretty much aligned and because we’re
both professional poker players we’re
very much used to thinking about all
kinds of things in terms of
probabilities even potentially emotional
topics like this one well I certainly
wasn’t always rational around
probabilities for example the very first
time I played poker it was 2005 and I
just graduated University from here in
Manchester and I didn’t really know what
I wanted to do with my life yet so
naturally I started applying for game
shows and if I how I got on yeah first I
got on turned out to be a reality show
that took five beginners and taught them
how to play poker and well I was one of
those beginners and then we would
compete for a winner-take-all prize of
$100,000
specially for a graduate with a ton of
debt so in one of the first games we
start playing and I get dealt two aces
which are the best starting hand in
poker and before I knew it I got on all
my chips in the middle and then my
opponent they get really lucky and it’s
a miracle quad and I’m out of the game
but it’s fine because I handle it with a
also I wish no in fact I love having a
complete meltdown to cry at the tables
and embarrass myself on national TV and
why did I do that well I did it because
I was shocked even though I’ve been told
to expect that aces will lose around 20%
of the time my internal dial
very much didn’t feel like a 20% of
so fortunately I’ve gotten my act
together a bit more since then and
that’s largely because well poker
teaches you to get used to bad luck if
you play the game often enough you’ll
expect to see maybe hundreds of
thousands of hands over a given year and
so you’ll see all these crazy wondrous
centers and freak events happen with the
cards over and over
that’s because probabilities compound
while the likelihood of one individually
unlucky event happening in to us is
small in a given year like getting our
phone stolen or being made redundant
having one of our five closest relatives
die if you start thinking about all the
events that you could consider to be
unlucky then actually the chances build
up and up until it’s quite likely that
one of them happens and while this might
seem kind of depressing I found that
remembering this mathematical fact has
helped me manage my expectations better
because then I’m less shocked and when
we’re less shocked then we’re better
able to reason through a tough situation
and not spend so much of our time
thinking about negative unhelpful
thoughts like why me why am I so unlucky
now I’m not suggesting you’ll go out and
learn to play poker to get used to bad
luck but it is important to remember to
look at life through a probabilistic
lens because as incredible physicist
Richard Feynman once said nature permits
us only to calculate probabilities and
yet science does not collapse
and what he means by this is that the
the world around us kind of like a card
game is ultimately governed by the laws
of chance and statistics even even the
fundamental nature of matter that
particles whizzing around in our bodies
in everything in this room appeared to
behave in terms of probabilities and our
universe is just full of all this
complexity and yet through science for
the process of observation and evidence
and reason we can learn to make
remarkably accurate predictions by using
these probabilities but we are not all
perfect scientists in fact far from it
we make many mistakes in how we think
and speak around problem
and it’s some of these mistakes that I
want to talk to you guys about today so
the first of these is our tendency to
assume that something is a certainty
when it’s not in other words to assign a
hundred percent probability to something
but hundred assem probabilities are
extremely extremely rare and this is
known as the overconfidence bias where
we tend to be over confident in the
strength of our beliefs and convictions
and this can lead us to a cardinal sin
gambling without even realizing that
we’re gambling and perhaps the best
example of this is the 2008 financial
crisis which was largely contributed to
by the assumption that the house prices
across the entirety of the u.s. couldn’t
all go down at the same time but they
could and they did and it was that that
kick-started the Cheney action that
created the largest economic disaster
since the Great Depression
and it’s because we knew of this bias
the Igor and I you decided to ask each
other that all the question about
whether we think will be to get all the
likelihood that we’ll be together in
three years time because we’re now at
that critical stage where we’re thinking
about things like marriage and buying a
house together or maybe moving country
and well imagine if we went full steam
ahead assuming we’re a hundred percent
to be together but maybe your percentage
is actually only sixty percent so it’s
crucially important so take a moment a
question what is your fit you think
you’re certain about especially if it’s
to do with your relationships then well
we have to have these frank and
quantified discussions from time to time
with our loved ones about things that
all these potential worst cases I like
to think of it as taking an insurance
policy out on your emotions where you
you pay the the awkward premium up front
but you’re then better safeguarded
should the worst case happen and another
mistake returned today make is we tend
to treat near certainties to simile to
one another so if you look at these two
percentages they look kinda the same
right but chilly there’s a huge
difference between the two for example
if all the nuclear reactors in the world
had a safety rating of a instead of B
and instead of us having a 50/50 chance
of some kind of nuclear accident every
fifteen years we’d expect to have one
every 1.5 years
now would obviously be a huge huge
problem fortunately nuclear powers safer
than both of these but this this this
thing that we do where we we tend to
treat these fringe fringe cases a little
bit too similarly can lead us to another
sin and that’s gambling for sakes we
can’t afford certainly something I’ve
seen a lot of in poker and an example of
this is skiing when I was a kid went
skiing
we never wore helmets this was back in
the 90s and they just weren’t even
offered to us and I wasn’t because
helmets were super expensive or anything
it’s just more because well no one
really thought through these very remote
but potentially worst-case disasters of
getting your head in the slow and what
could actually happen but nowadays of
course we know better and it makes you
wonder what what are other things in
life that could be a helmet worth
wearing maybe it’s just making sure we
go for those regular cancer screenings
or simply putting a bath mat down in our
shower well just make sure you don’t eat
that piece of pizza while you’re driving
have it when you get home and doesn’t we
tend to oversimplify how we think about
probabilities we can let that slip into
our language too for example you always
make us late because you don’t give me
enough time to get ready
oh yeah that’s because you’re always on
the phone with your friend well that’s
because you just never actually spend
any time listening to me well that’s
because you always precise me that’s
because you never get anything right
these conversations they they can
escalate somewhat and that’s because
we’re speaking these at absolutes we’re
trying out these always is in these
Nevers and they’re very
counterproductive if you say to someone
you you never take any time for me
you’re naturally saying they have never
spent any effort on you and no one likes
being accused of something that just
clearly isn’t true so then they’ll
become all defensive and so they’ll take
the easy route out of questioning the
the accuracy of your statement instead
of actually taking the time to discuss
the change change you want when we do
finally try and speak probabilistically
in our languages in our language we’re
really bad at that as well take for
example the
raise a fair chance if I was to say to
you there’s a fair chance of rain
tonight what’s the first number that
pops into your head
well I asked this same question on
Twitter and I got around 300 responses
and this was the range of answers huge I
got answers from everywhere from 18% all
the way up to 90% and yet back in 1961
the exact words fair chance of success
weather year the words used by the Joint
Chiefs of Staff
when briefing President Kennedy about
the their estimations of a success of an
invasion of Cuba they had met with
military experts and they reckoned it
there was Rankin three-to-one against
chance so in other words only a 25%
chance of success if they were just
saying that to Kennedy the staff told
him there’s a fair chance in his
interpretation of that was
understandably more positive well it’s
not certain from history if that was
being exactly it some of the deciding
factor we do know that the u.s. soon
launched after the the Bay of Pigs
invasion which was a complete
catastrophe that took the world one step
closer to nuclear war so if this vague
unquantified language can cause blunders
like that at the highest levels of
office imagine the frequency of
miscommunications we must all be making
in our daily lives we expect that our
products will launch within the next
three months okay she’ll probably be
home for dinner
so we’ve all been in trouble saying
something like that and that’s because
we all have very different
interpretations of these vague
probabilistic words words like probably
or frequently or likely and again Iran
similar polls on Twitter and this was
the distribution of answers even
and then then we have the really bad
words these are known as weasel words I
guess but there’s a chance that maybe
possibly we could do this oh these words
are so bad to actually say anything we
should just scrub them from the language
all together you ask me but if we do
want to use them then we should only do
it when we are deliberately pretending
to convey information but we know that
we’re not well most the time we are
vague with our language at a sheer
unconscious habit but this habit makes
us intellectually dishonest with
ourselves and it opens us up to biases
like the hindsight bias or the illusion
of transparency where we think we’re
being better understood than we actually
are
and so now I’ve taken I’ve tried to
build the habit in myself to quantify
any any of these fuzzy words when I
catch myself using them for example if a
friend says to me hey Liv what do you
think do you think you are gonna be able
to make the time to help me out with
that thing tonight instead of just
saying
yeah sure probably I’ll give them an
estimation or say 90% because even if it
feels even if it feels like I guess it’s
still better than leaving it undefined
for them because when we say a number we
know that they’ll hear that number but
if we use words we don’t actually know
what lands in the other person’s brain
and a handful of industries have taken
to defining they’re commonly used
trouble words take the pharmaceutical
industry for example this is the list of
standard definitions of words relating
to the frequency of side-effects is what
you might expect to see in your packet
of paracetamol at home and it makes good
sense because otherwise we wouldn’t be
out of assess the risks to ourselves
properly and I propose we come up with
our own set of definitions as well
what if we could all agree to use these
as a guideline in our daily lives or
maybe in our workplaces or even get the
media to use them because if it was to
actually mean something then we need to
have a mutual understanding of what they
stand for but ultimately if there’s a
situation when we can use a number then
we really should do and it makes me sad
the society has taught us to think that
speaking in numbers is nerdy and uncool
because there’s a awesome
they give us clarity and granularity and
help us up like way up our options
better in the face of uncertainty and
you will remember that scene in the
matrix where neo has that the best bit
where he has that breakthrough where he
starts seeing the whole world as it
really is and all the little green bits
of code trickling down well we too can
learn to see the world in probabilities
you can and then when we do we’ll
actually be better equipped to handle
all the good and bad luck that life
might throw at us because one will never
be certain of which path our future will
take we can control the likelihoods of
the paths that we want thank you
[Music] you