Do we see the world as it really is
[Music]
okay uh
thank you thank you very much indeed um
so the theme of
the theme of today’s session uh is
distortion
and as i was thinking about this uh it
occurred to me that the very concept of
distortion
implies that there’s an original or a
real version of something
and a distorted version and
that sort of line of thinking about the
being an original or a real version
versus a distorted version really begs
or
poses or brings up one of the very
oldest questions in psychology and
philosophy
which is of course do we see the world
as it really is
so do our powers of perception and
reason
really give us a sound and accurate
picture of the world
or is it the case that our perceptions
and our
reasoning uh are always incomplete
and flawed so that perhaps we are only
ever able to gain an incomplete
or perhaps a picture a picture of a
shadow of reality
which is really what plato thought uh
approximately two and a half thousand
years ago
of course the everyday answer the
everyday answer to this question is that
perception certainly
seems to work perfectly accurately and
perfectly well
despite all the glare i can see a world
of people i can
open my eyes and see a world of people
and objects and be very very confident
that i can take
a few steps forward and walk around the
obstacles in front of me pick
up the objects and talk to the people
talk to the people that are here
so so perception seems to work
perfectly well we seem to open our eyes
it seems simple and effortless
but is it really that simple is it is it
really that straightforward
well an approach which is available to
us here in the 21st century which of
course wasn’t available
to plato uh and his contemporaries is to
look inside the skull and ask well how
much brain power
is involved in the apparently simple act
of just opening our eyes
and looking out at the world well if we
look at
if we do look inside the skull what we
can see is the
is the surface of the cerebral cor the
surface of the brain cerebral cortex
is divided into four main lobes as we
can see here the occipital parietal
frontal and temporal lobes and it
turns out that all four of those lobes
of the cerebral cortex are critically
important for vision not only that
of course underneath the cortex there’s
a whole range of subcortical brain
structures
and it turns out that several of those
are also
critically important for vision
so uh i’ve always been very surprised by
this it’s always been surprising to me
that so much of the brain
which we think of as our organ of
thinking uh
is really devoted to this apparently
simple task
of just seeing of of perceiving the
world
of course on the other hand it’s also
true that when we think
about thinking and when we talk about
thinking
we often do that in highly visual terms
we talk about ideas that are opaque or
hazy
or perhaps crystal clear we talk about
theories that may be insightful
or enlightening and we talk about people
who are very bright
or perhaps if we want to insult them we
might say that they’re a bit dim
so so perhaps you can see what i mean
here you can and you can see
where i’m going so so vision is
something that in our everyday lives we
take completely for granted
and we use phrases such as seeing is
believing
on the other hand perhaps
like the character neo in the classic
movie the matrix
we can occasionally become aware of
become aware of
little cracks and fissures in the
structure and sort of coherent
of our visual reality so if we look at
this picture here which is a still from
the matrix we can see that neo
uh is holding up four fingers and i hope
that all seems completely obvious to you
he’s holding up four fingers there and
if we move to this slide and i ask you
again
how many fingers am i showing you here
again the answer seems completely
obvious
well obviously there’s three but if we
look at a more complete picture
uh we can see what but well actually
perhaps the answer might be
two well you might say well
well that’s just a visual trick let’s
look at something a bit more
straightforward let’s
let’s just get this straight and if i
ask you are these lines
perfectly are these lines straight and
parallel
again the answer seems very obvious
obviously they’re
they’re straight and parallel um but
what about these ones if we look at
these ones do you think these ones are
straight and parallel
well as i look at them there’s no way
that they look straight and parallel
they seem to be sort of waving all over
the place
but if we superimpose the two slides
we can see that in fact both sets of
lines
are perfectly straight and perfectly
parallel
so this is a very well known illusion
it’s called the cafe wall illusion and
it’s called that
because this man here very eminent uh
british psychologist called richard
gregory
was having his lunch one day several
many decades ago in bristol
and he glanced across and saw this uh
this particular cafe wall actually
noticed the illusion described it and
then studied it
and a little bit a little bit closer to
home actually here so here’s a much more
scaled up version of the cafe wall
illusion
uh which i believe you can see on the
side of this building
in melbourne okay so uh
so perhaps seeing isn’t always believing
and one of the things that has a strong
influence in
on how we see things is the context in
which we see them
so if we look at these two orange discs
here on this slide
this is another very well known illusion
called the ebbinghaus illusion
we can see that the one on the right one
on the right looks relatively big the
one on the left looks relatively small
but of course they’ll be looking at the
one on the right in the context of these
somewhat small little gray little gray
discs whereas the one on the left is
we’re
looking at that in the context of these
much larger discs
and if we take that context away what we
can see
is that in fact the two discs are
exactly the same
size so it turns out that context
that context can have some very powerful
influences on the way
we see things we often talk about
people who see things in black and white
and the reason we say that
is that black and white do seem like
such polar opposites and you couldn’t
possibly argue
you know that black is white or that
white is black
but let’s just have a look at this
illustration here which is a very clever
demonstration developed
by a vision scientist called edward h
adelson
so what we can see here is a black and
white
checkerboard and if i ask you
which of these two squares is darker
square
a or square b so which one looks darker
well i hope you’ll agree
that a clearly looks quite a bit darker
but if we look at this illustration a
little
more carefully what we can see is that
we’re looking at
b inside the shadow that’s being cast by
this
large uh green cylinder
so let’s just see if a is really darker
than b
by taking away the visual context
of the rest of the figure including the
shadow so let’s leave the
lose the left hand side the right hand
side
some of the context around the two
squares and we take away the last little
bit
and we can see that in fact a and b are
exactly the same brightness
so we can argue actually that black is
white and white is black
and it’s not in and it’s not an entirely
silly thing to uh
to say and just to show you that there’s
no there’s no real jiggery poker here
keep looking at a and b and let’s put
the context back in and as we add in the
shadows and the rest of the figure
you can see that when we add the context
add the context back in again again
a looks totally different to b okay
so what we can see from this uh is that
context can have these very
powerful effects on the way we see
things visually
so what about how we see the world of
ideas and beliefs
can context also have powerful effects
in that more abstract
cognitive domain and i’ll illustrate uh
i’ll illustrate this by talking about a
very well known study
carried out by these two psychologists
here daniel kahneman and amos taversky
and as many of you will know uh kahneman
went on several years
several years after this study was many
years after this study was published to
uh
to win the nobel prize so back in the
early 1970s
kahneman and tversky dreamt up this
scenario
which as you can see is uh spookily
relevant
to the situation in which we find
ourselves today
what they asked their research
participants to do
was to imagine that the country they
were in new zealand in this case
is preparing for the outbreak of an
especially
virulent virus and people were told if
urgent steps are not taken
we’re going to lose 600 lives
so then the participants were asked were
presented with this
choice they were asked to choose whether
or not we should adopt
program a or program b so pro so the
programs could be to do with
alternative vaccines or it could be to
do with lockdown
protocols and so on uh some procedure
for reducing the impact of the virus
and what the people were told was well
if we go with program
a 200 people are going to be saved
whereas if we go with program b there’s
a one in three probability that 600
people will be saved and a two in three
probability
that no people will be saved so when
faced
with that choice a large majority
72 percent chose program a
they preferred the certainty of saving
those 200 lives however
what kahneman and tversky also did was
to recruit a second group of
participants
and and the second the second group was
given this
choice they were told if we adopt
program a
400 people are going to lose their lives
whereas if we adopt program b we have a
one in three probability that no one
will die
and a two in three probability that 600
people will die
when faced with these choices a
similarly large majority in fact a
slightly larger majority
went for program b but if you look at
these
alternatives carefully or even not that
carefully you can see that in fact the
information is exactly the same
losing 400 400 of the 600 lives is
exactly the same
as saving 200 of the 600 lives and the
information in pro
for program b is also in fact identical
so what we can see from this uh is that
is that if we present uh essentially
identical phrase
identical information in different
frameworks in different
contexts we can produce radical changes
in people’s preferences
and judgments so if we present
yeah we can produce these very strong
changes
just by changing whether or not we
present the information in terms of
saving lives or in terms of losing lives
so we’ve got an election coming up here
in a few weeks time and i gather there’s
another election
happening in america at the beginning of
november
and of course if any of the candidates
and parties in those
elections won a majority in the mid or
high
70 percents they’d be absolutely
delighted and ecstatic
so so what we can see from this
is is that these context effects can
produce very powerful and very dramatic
effect
very dramatic influences uh on people’s
preferences
so context can be critical in perception
even when you’re judging something that
seems simple and straightforward
such as how bright something is how
large something is
whether or not we have a straight line
but also
when we’re making these complex
high-level judgments
about what we should do when faced with
a global pandemic
so so what what can we learn from this
what can we conclude from this
you might be a little bit worried at
this point and think well
can we ever really trust our own
perceptions and our own judgments
is our view of the world really at the
mercy
of the particular and specific context
that we just happen to find ourselves in
you might worry and feel like w b yates
that you’re
that your head is spinning uh at this
point because
the things you thought you could see
clearly and the foundations of your
beliefs and judgments perhaps suddenly
they don’t seem so
firm anymore and perhaps they’re
suddenly more fragile
and and perhaps prone to disintegrating
well i think that would be that would be
a very negative con
a very negative uh conclusion but i and
i think there’s a much more
positive way of thinking about
the way in which context can influence
our perceptions and our judgments and
i’d like to illustrate that
by stepping away from psychology for a
few moments and stepping into the realm
of physics
and of course the the second part of our
question is really centrally about the
nature of the world and of course
questions about the nature of the world
are really really in the province of
physics
not the province of psychology so um
back in 2016 uh this man here carla
rivelli
wrote a fascinating book called reality
is not what it seems and one of the
points that ravelli
made in this book is that we can view
reality from multiple perspectives
so we have our everyday perspective
where we have a world of
solid objects
objects appear solid there and they
exist at a particular
place in a particular location in space
and at a particular point in time but
ravelli points out that that breaks down
completely
when we start to think about what’s
happening at the
almost unimaginably tiny uh
tiny spatial scale and brief time scale
of the way in which fundamental
particles interact with each other
and of course our perceptions of time
and space are also radically different
when we consider
the the much the almost unimaginably
large time scales where stars and whole
galaxies
may form so so reality so we can see
reality from multiple perspectives
so so i think the the the message that
i’d like to
finish with is to say that
when we approach a really big question
such as do we see the world as it really
is we’re very unlikely to get a complete
answer
by looking at it from a single
perspective if we want
if we really want to gain a more
complete uh
a better and more complete answer we’re
going to
we’re almost certainly going to need to
step out of our own
uh particular contextual silo as it were
and that silo
might be your at your own academic or
scientific discipline
of course we of course at the moment
we’re living
in in very difficult and challenging and
potentially very divisive
times so perhaps there’s also a more
perhaps there’s also a broader lesson to
to learn here about trying to think
about
issues from a different perspective and
of course that different perspective
might be the perspective of somebody
who’s at the opposite end of the
political spectrum to the
to the location where you are or it
might be somebody from a different
social or cultural
group psychologists refer to this as
perspective
taking the ability to see something
as it might be seen from a different
point of view
and recently the neuroscience of
perspective taking it has
made some quite interesting advances by
looking at the brain regions that become
active
when you imagine looking at a visual
object
from a different point of view or if you
imagine
adopting a different belief from the
belief that you currently
hold and interestingly uh some
very common areas are lighted up when
you do both of those things when you
imagine a different visual point of view
and you imagine a different cognitive
point of view
so that’s perspective taking it it
emerges quite early in childhood
in stages between the ages of about two
and
five years old um and the final thought
i’d like to leave you with
is that we know that young children can
do perspective
taking but perhaps it also might be
something that’s been
going to be very beneficial and helpful
for us to practice that a little bit
more
as adults as well as as well as when we
were children
and that’s and thank you very much for
listening