Waspish behaviour
How
Sphex
came to be linked with free will
is a long story. Charles Darwin was studying
this wasp while working on his theory of
evolution. We know from his notebooks that
its behaviour had a big impact on him. He
wasn’t aware that it would ceaselessly check
its burrow – that discovery was made decades
later by Nikolaas Tinbergen, the founder of
ethology, the science of animal behaviour.
What interested Darwin was what the wasp
does once it has dragged a cricket into its
burrow: it lays its eggs in the body of the
immobilised but still living prey. When the
larvae hatch they eat it from the inside out.
Darwin was so appalled by this behaviour
that he cited it as one reason for his loss
of faith. “I cannot persuade myself that
a beneficent & omnipotent God would
have designedly created the Ichneumonidae
with the express intention of their feeding
within… living bodies,” he wrote. Meanwhile,
his theory wasn’t just undermining God.
Some took it as support for the idea that
humans are mere animals and that animals
are mere machines, fanning the flames of
a millennia-old debate about free will.
To Darwin,
Sphex
was emblematic of the
cruelty found in nature. Tinbergen exposed
it as emblematic of nature’s mindlessness. But
it was the philosopher Daniel Dennett of Tufts
University in Massachusetts, who coined the
word “sphexishness” to describe the nature
of human choices if we say they are like those
of other animals. In doing so, he highlighted
a common misconception: that we must
either reject the idea that biology influences
our choices or reject the notion of free will.
This fallacy is the nub of the problem.
Biology certainly influences our choices, as
plenty of evidence shows. Perhaps the most
famous example is an experiment on free
will done in the 1980s by Benjamin Libet. He
showed that brain activity associated with an
action occurs before the subjective feeling of
choosing that action. More recently, Libet’s
experiment was replicated with the addition
of an functional MRI scanner. This time, the
researchers were able to predict some actions
from brain activity up to 10 seconds before
a conscious decision was taken. If the brain
activity precedes the feeling of choice, some
have argued, all choosing is just an illusion.
These results aren’t the great challenge to
free will that they might seem at first. Their
apparent force relies on misguided intuitions
about what it means to have free will. We tend
to think in terms of the self versus other causes.
And we assume that the more of these other
causes that are involved in the decision-making
process, the less self-determination, or free
will, is involved. The misconception arises
because we have difficulty comprehending
causation in complex systems. We tend to
think about cause and effect as a one-to-one
relationship: A causes B. In reality, it is always
a set of things happening (or not happening)
that cause another set of things to happen (or
not happen). Discovering that A was involved
in causing B doesn’t mean that other factors
aren’t important too.
Causality encompasses everything from
your genes to your ideas about the future. As
we find out new facts about genes and brains,
the space in which your self exists – your
free will, responsibility and choices – doesn’t
diminish. This is something I have been
pondering for years. What really brought it
home to me was interacting with a complex,
chaotic system called a cellular automaton,
and seeing that the simplest of rules can
generate an endless, unpredictable set of
behaviours. This is a grid world created on
a computer with basic rules for changing
each tile in the grid from black to white
and vice versa. With the right rules and the
right starting conditions, it can generate an
infinite number of unpredictable patterns.
Seeing, from so simple a beginning, endless
forms being born, made me realise that the
fear we are sphexish is baseless. There is no
need to worry that something as complex as
a human can be caught in a meaningless loop.
It was to explore these ideas and more,
that I created The Choice Engine. You can
find this interactive essay by tweeting
@ ChoiceEngine START, and the bot will guide
you, letting you choose your own unique
path through the story, following the areas
that most interest you. In it, I argue that
our intuitions mean that the problem of
free will never feels solved, but it is. The
solution is that we are part of nature – we
are complex machines. If you change your
intuitions about what such a machine can
do, and what those actions can mean, then
you realise that we are free to make real
meaningful choices. Yes, our thoughts are
caused by our brains, our environment
and our history, but this causal mix is
unique to each individual at each moment.
That explains why human behaviour is so
difficult to predict.
My career researching the brain and how
we choose has made me optimistic that we
do have free will. Darwin’s theory of evolution
gave us a fear of being mere creatures. I simply
disagree with the word “mere”. There is enough
tangled complexity in relation to the brain
and mind that we can retain a meaningful
view of free will and at the same time
recognise our nature as living machines.
■
Tom Stafford
is at the University of Sheffield, UK.
To explore his Choice Engine on Twitter, tweet
@ ChoiceEngine START
“ Simple rules can generate
an endless, unpredictable
set of behaviours”
The digger wasp can get trapped in inflexible
behaviour, but does that mean it lacks free will?
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