Alright
Herr Doktor Professor, you are giving me too much homework.
David :-)
“No free man shall ever be debarred the use
of arms. The
strongest reason for the people to retain the right to
keep and bear arms is,
as a last resort, to protect themselves against tyranny in
government”--Thomas
Jefferson
On 1/17/2013 8:55 AM, [email protected] wrote:
from the site :
io9 we come from the future
Scientific evidence that you probably don’t have free will
Humans have debated the issue of free will for
millennia. But over the past several years, while the
philosophers continue to argue about the metaphysical
underpinnings of human choice, an increasing number of
neuroscientists have started to tackle the issue head on —
quite literally. And some of them believe that their
experiments reveal that our subjective experience of
freedom may be nothing more than an illusion. Here's why
you probably don't have free will.
Indeed, historically speaking, philosophers have had
plenty to say on the matter. Their ruminations have given
rise to such considerations as cosmological determinism
(the notion that everything proceeds over the course of
time in a predictable way, making free will impossible),
indeterminism (the idea that the universe and our actions
within it are random, also making free will impossible),
and cosmological libertarianism/compatibilism (the
suggestion that free will is logically compatible with
deterministic views of the universe).
Now, while these lines of inquiry are clearly important,
one cannot help but feel that they're also terribly
unhelpful and inadequate. What the debate needs is some
actual science — something a bit more...testable.
And indeed, this is starting to happen. As the early
results of scientific brain experiments are showing, our
minds appear to be making decisions before we're
actually aware of them — and at times by a significant
degree. It's a disturbing observation that has led some
neuroscientists to conclude that we're less in control of
our choices than we think — at least as far as some basic
movements and tasks are concerned.
At the same time, however, not everyone is convinced. It
may be a while before we can truly prove that free will is
an illusion.
Bereitschaftspotential
Neuroscientists first became aware that something curious
was going on in the brain back in the mid 1960s.
German scientists Hans
Helmut Kornhuber and Lüder Deecke discovered a
phenomenon they dubbed "bereitschaftspotential"
(BP) — a term that translates to "readiness potential."
Their discovery, that the brain enters into a special
state immediately prior to conscious awareness, set off an
entirely new subfield.
After asking their subjects to move their fingers (what
were self-initiated movements), Kornhuber and Deecke's
electroencephalogram (EEG) scans showed a slow negative
potential shift in the activity of the motor cortex just
slightly prior to the voluntary movement. They had no choice
but to conclude that the unconscious mind was initiating a
freely voluntary act — a wholly unexpected and
counterintuitive observation.
Needless to say it was a discovery that greatly upset the
scientific community who, since the days of Freud, had
(mostly) adopted a strictly deterministic view of human
decision making. Most scientists casually ignored it.
But subsequent experiments by Benjamin Libet in the 1980s
reinforced the pioneering work of Kornhuber and Deecke.
Similarly, Libet had his participants move their fingers,
but this time while watching a clock with a dot circling
around it. His data showed that the readiness potential
started about 0.35 seconds earlier than participants'
reported conscious awareness.
He concluded that we
have no free will as far as the initiation of our
movements are concerned, but that we had a kind of
cognitive "veto" to prevent the movement at the last moment;
we can't start it, but we can stop it.
From a neurological perspective, Libet and others
attributed the effect to the SMA/pre-SMA and the anterior
cingulate motor areas of the brain — an area that allows us
to focus on self-initiated actions and execute
self-instigated movements.
Modern tools show the same thing
More recently, neuroscientists have used more advanced
technologies to study this phenomenon, namely fMRIs and
implanted electrodes. But if anything, these new experiments
show the BP effect is even more pronounced than previously
thought.
For example, a
study by John-Dylan Haynes in 2008 showed a similar
effect to the one revealed by Libet. After putting
participants into an fMRI scanner, he told them to press a
button with either their right or left index fingers at their
leisure, but that they had to remember the letter that was
showing on the screen at the precise moment they were
committed to their movement.
The results were shocking. Haynes's data showed that the BP
occurred one entire second prior to conscious awareness — and
at other times as much as ten seconds. Following the
publication of his paper, he
told Nature News:
The first thought we had was 'we have to check if this is
real.' We came up with more sanity checks than I've ever
seen in any other study before.
The cognitive delay, he argued, was likely due to the
operation of a network of high-level control areas that were
preparing for an upcoming decision long before it entered
into conscious awareness. Basically, the brain starts to
unconsciously churn in preparation of a decision, and once a
set of conditions are met, awareness kicks in, and the
movement is made.
In another study, neuroscientist Itzhak Fried put aside the
fMRI scanner in favor of digging directly into the brain (so
to speak). To that end, he implanted
electrodes into the brains of participants in order to
record the status of individual neurons — a procedure that
gave him an incredibly precise sense of what was going on
inside the brain as decisions were being made.
His experiment showed that the neurons lit up with activity
as much as 1.5 seconds before the participant made a
conscious decision to press a button. And with about 700
milliseconds to go, Fried and his team could predict the
timing of decisions with nearly 80% accuracy. In some
scenarios, he had as much as 90% predictive accuracy.
Different experiment, similar result.
Fried surmised that volition arises after a change in
internally generated fire rates of neuronal assemblies cross
a threshold — and that the medial frontal cortex can signal
these decisions before a person is aware of them.
"At some point, things that are predetermined are admitted
into consciousness," he told
Nature, suggesting that the conscious will might be
added on to a decision at a later stage.
And in yet another study, this one by Stefan Bode, his
detailed fMRI experiments showed that it was possible
to actually decode the outcome of free decisions for several
seconds prior to it reaching conscious awareness.
Specifically, he discovered that activity patterns in the
anterior frontopolar cortex (BA 10) were temporally the
first to carry information related to decision-making, thus
making it a prime candidate region for the unconscious
generation of free decisions. His study put much of the
concern about the integrity of previous experiments to rest.
The critics
But not everyone agrees with the conclusions of these
findings. Free will, the skeptics argue, is far from
debunked.
Back in 2010, W.
R. Klemm published an analysis in which he complained
about the ways in which the data was being interpreted, and
what he saw as grossly oversimplified experimentation.
Others have criticized
the timing judgements, arguing about the short
timeframes between action and movement, and how attention to
aspects of timing were likely creating distortions in the
data.
It's also possible that the brain regions being studied,
namely the pre-SMA/SMA and the anterior cingulate motor
areas of the brain, may
only be responsible for the late stages of motor planning;
it's conceivable that other higher brain systems might be
better candidates for exerting will.
Also, test subjects — because of the way the experiments
were set up — may have been influenced by other
"choice-predictive" signals; the researchers may have been
measuring brain activity not directly related to the
experiment itself.
The jury, it would appear, is still out on the question of
free will. While the neuroscientists are clearly revealing
some important insights into human thinking and decision
making, more work needs to be done to make it more
convincing.
What would really settle the issue would be the ability for
neuroscientists to predict the actual outcome of more
complex decisions prior to the subject being aware of it
themselves. That would, in a very true sense, prove that
free will is indeed an illusion.
Furthermore, neuroscientists also need to delineate between
different types of decision-making. Not all decisions are
the same; moving a finger or pressing a button is very
different than contemplating the meaning of life, or
preparing the words for a big speech. Given the limited
nature of the experiments to date (which are focused on
volitional physical movements), this would certainly
represent a fruitful area for inquiry.
Blurring science, philosophy, and morality
Moreover, there's also the whole issue of how we're
supposed to reconcile these findings with our day-to-day
lives. Assuming we don't have free will, what does that say
about the human condition? And what about taking
responsibility for our actions?
Daniel Dennett has recently tried to rescue free will from
the dustbin of history, saying that there's still some elbow
room for human agency — and that these are still scientific
questions. Dennett, acknowledging that free will in the
classic sense is largely impossible, has attempted to
reframe the issue in such a way that free will can still be
shown to exist, albeit under certain circumstances. He writes:
There's still a lot of naïve thinking by scientists about
free will. I've been talking about it quite a lot, and I do
my best to undo some bad thinking by various scientists.
I've had some modest success, but there's a lot more that
has to be done on that front. I think it's very attractive
to scientists to think that here's this
several-millennia-old philosophical idea, free will, and
they can just hit it out of the ballpark, which I'm sure
would be nice if it was true.
It's just not true. I think they're well intentioned.
They're trying to clarify, but they're really missing a lot
of important points. I want a naturalistic theory of human
beings and free will and moral responsibility as much as
anybody there, but I think you've got to think through the
issues a lot better than they've done, and this, happily,
shows that there's some real work for philosophers.
Dennett, who is mostly responding to Sam
Harris, has come under criticism from people who
complain that he's being epistemological rather than
scientific.
Indeed, Sam Harris has
made a compelling case that we don't have it, but that it's
not a problem. Moreover, he argues that the ongoing belief
in free will needs to come to an end:
A person's conscious thoughts, intentions, and efforts at
every moment are preceded by causes of which he is
unaware. What is more, they are preceded by deep causes —
genes, childhood experience, etc. — for which no one,
however evil, can be held responsible. Our ignorance of
both sets of facts gives rise to moral illusions. And yet
many people worry that it is necessary to believe in free
will, especially in the process of raising children.
Harris doesn't believe that the illusoriness of free will
is an "ugly truth," nor something that will forever be
relegated to philosophical abstractions. This is science, he
says, and it's something we need to come to grips with.
"Recognizing that my conscious mind is always downstream
from the underlying causes of my thoughts, intentions, and
actions does not change the fact that thoughts, intentions,
and actions of all kinds are necessary for living a happy
life — or an unhappy one, for that matter," he writes.
But as Dennett correctly points out, this is an issue
that's far from being an open-and-shut case. Advocates of
the "free will as illusion" perspective are still going to
have to improve upon their experimental methods, while also
addressing the work of philosophers, evolutionary biologists
— and even quantum physicists.
Why, for example, did humans evolve consciousness instead
of zombie-brains if consciousness is not a channel for
exerting free will? And given the nature of quantum
indeterminacy, what does it mean to live in a universe of
fuzzy probability?
There's clearly lots of work that still needs to be done.
Centroids: The Center of the Radical Centrist Community
<[email protected]>
Google Group: http://groups.google.com/group/RadicalCentrism
Radical Centrism website and blog: http://RadicalCentrism.org
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Centroids: The Center of the Radical Centrist Community <[email protected]>
Google Group: http://groups.google.com/group/RadicalCentrism
Radical Centrism website and blog: http://RadicalCentrism.org
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