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Neuroscience, free will and determinism: 'I'm just a machine'

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  • medit8ionsociety
    Neuroscience, free will and determinism: I m just a machine Our bodies can be controlled by outside forces in the universe, discovers Tom Chivers. So where
    Message 1 of 1 , Oct 14, 2010
      Neuroscience, free will and determinism: 'I'm just a machine'

      Our bodies can be controlled by outside forces
      in the universe, discovers Tom Chivers. So where does that leave free will?

      For a man who thinks he's a robot, Professor
      Patrick Haggard is remarkably cheerful about it.
      "We certainly don't have free will," says the
      leading British neuroscientist. "Not in the sense
      we think." It's quite a way to start an interview.

      We're in the Institute for Cognitive Neuroscience,
      in Queen Square in London, the nerve centre –
      if you will – of British brain research. Prof Haggard is demonstrating "transcranial magnetic stimulation",
      a technique that uses magnetic coils to affect
      one's brain, and then to control the body. One
      of his research assistants, Christina Fuentes,
      is holding a loop-shaped paddle next to his
      head, moving it fractionally. "If we get it right,
      it might cause something." She presses a switch,
      and the coil activates with a click. Prof Haggard's
      hand twitches. "It's not me doing that," he assures
      me, "it's her."

      The machinery can't force Prof Haggard to do
      anything really complicated – "You can't make
      me sign my name," he says, almost ruefully –
      but at one point, Christina is able to waggle
      his index finger slightly, like a schoolmaster.
      It's very fine control, a part of the brain
      specifically in command of a part of the body.
      "There's quite a detailed map of the brain's
      wiring to the body that you can build," he tells me.

      I watch as Christina controls Prof Haggard's
      fingers like a marionette. The mechanical nature
      of it is unsettling. A graph on a screen shows
      his muscle activity plotted by time; 20 milliseconds
      after she clicks the button, it depicts an elegant
      leap and drop, like a heartbeat on an ECG. That
      20 milliseconds is how long it takes for the
      signal to travel down his nerves. "The conduction
      time would be less from my jaw muscles, more from
      my leg muscles," he says. And as many of us will
      recognise, the process gets less effective as
      we age: "As I get older, the curve will move slowly
      to the right on the graph."

      The idea that our bodies can be controlled by an
      outside force is a pretty astonishing one. "This
      is absolutely out of my control," insists
      Prof Haggard, as his muscles continue to move.
      "I'm not doing it, Christina is. I'm just a machine,
      and she is operating me."

      What does this mean in terms of free will? "We don't
      have free will, in the spiritual sense. What you're
      seeing is the last output stage of a machine. There
      are lots of things that happen before this stage –
      plans, goals, learning – and those are the reasons
      we do more interesting things than just waggle fingers.
      But there's no ghost in the machine."

      The conclusions are shocking: if we are part of
      the universe, and obey its laws, it's hard to see
      where free will comes into it. What we think of as
      freedom, he says, is a product of complexity.
      "An amoeba has one input, one output. If you touch
      it with one chemical, it engulfs it; with another,
      it recoils.

      "If you see a light go green, it may mean press
      the accelerator; but there are lots of situations
      where it doesn't mean that: if the car in front
      hasn't moved, for example. The same stimulus sometimes
      makes me press the accelerator, but sometimes the
      horn. We are not one output-one input beings; we have
      to cope with a messy world of inputs, an enormous
      range of outputs. I think the term 'free will'
      refers to the complexity of that arrangement."

      Slowly, however, we are learning more about the
      details of that complexity. This, Prof Haggard
      says, has profound implications: philosophically,
      morally, and – most worryingly – legally. "We understand
      what brain areas are responsible for impulsive
      behaviour, and which bits are responsible for
      inhibiting that behaviour. There's a whole brain
      network associated with holding back from things you shouldn't do.

      "What happens if someone commits a crime, and it
      turns out that there's a lesion in that brain
      area? Is that person responsible? Is the damage
      to the machine sufficient for us to exempt them from
      that very basic human idea that we are responsible
      for our actions? I don't know." He refers to a major
      project in America, where "lawyers, neuroscientists,
      philosophers and psychiatrists are all trying to work
      out what impact brain science has on our socio-legal
      sense of responsibility".

      This runs shockingly contrary to the sense of freedom
      that we feel in terms of controlling our actions,
      on which we base our whole sense of self and system
      of morality. "As far as I know," says Prof Haggard,
      "all societies hold individuals responsible for their
      actions. Even in animal societies, individuals have
      reputations. Non-human primates adjust their behaviour
      according to how other animals will respond. Junior
      males will not steal from older males, because they
      know they'll get beaten up. That's the beginning of
      social responsibility; the awareness that your behaviour
      has effects on the behaviour of others, and can have
      good or bad consequences.

      "It's a rule that we need to have as social animals.
      You couldn't have society unless, if you do something
      wrong, you pay for it. The question is, what do we
      do when people don't have the brain machinery to play
      by the rules – or decide not to play by them? That's
      not a scientific question. That's a moral one."

      Maybe, I suggest, we've over-defined free will.
      Perhaps it doesn't exist in the mystical
      breaking-the-laws-of-the-universe way, but there
      is a sense in which this "me", this brain and body,
      responds to the world, reacts to information, tries
      to shape its environment; takes decisions. Can we
      not pull free will back to something more defensible?
      He taps his fingers.

      "Yes, interacting intelligently with your environment
      might be enough. The philosophical definition of free
      will uses the phrase 'could have done otherwise'.
      I picked up the blue cup; could I have picked up the
      white one? Given the initial conditions, the world
      as it was, could I have acted differently?

      "As a neuroscientist, you've got to be a determinist.
      There are physical laws, which the electrical and
      chemical events in the brain obey. Under identical
      circumstances, you couldn't have done otherwise;
      there's no 'I' which can say 'I want to do otherwise'.
      It's richness of the action that you do make, acting
      smart rather than acting dumb, which is free will."

      Some philosophers – Robert Kane, and, famously,
      Karl Popper and John Eccles – have held out hope
      that quantum indeterminacy, the randomness at the
      level of the universe's finest grains, could
      rescue true freedom.

      Prof Haggard is dismissive. "No one wants to be
      told they're just a machine. But there is simply
      nothing approaching convincing evidence for the
      quantum view. Popper and Eccles proposed that free
      will was due to quantum indeterminacy in the
      chemical messages that communicate between neurons.

      "But none of that happens at the quantum level.
      From a physics point of view, it's macro-level."
      Besides, quantum activity is purely random, and
      randomness gives you no more freedom than determinism does.

      Does this bother you, I ask? Being a machine?
      "I keep my personal and professional lives pretty
      separate," he says, smiling. "I still seem to decide
      what films I go to see, I don't feel it's
      predestined, though it must be determined somewhere in my brain.

      "There's an idea in theology that our free
      will places us next to God. Milton describes
      this beautifully in Paradise Lost. We like to
      think we're wonderful, that we have this marvellous
      capacity. But we should be more impartial: perhaps
      we overestimate the value and the excitement of
      having free will."

      On that note, I take my leave. Although really,
      I didn't have any choice.

      As this article is being posted for non-commercial
      use only, its use is under the Fair Use statutes.
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