If the Mind is this…
…Can we have Free Will?
Eddy Nahmias (Philosophy)
Neurophilosophy Meeting: March 20, 2007
Laying my cards on the table

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I am a physicalist: In some sense of “is”
I believe the mind is the brain.
I believe normal adult humans have (at least some)
free will and we are morally responsible for at least
some of our actions.
I believe neuroscience and the other sciences of
the mind are highly relevant to the question of
whether we have free will … and how much free will
we have.
But, I do not think these sciences are relevant for
the reasons many scientists seem to think. In fact,
I think that they tend to get the issues confused…
Scientists suggest
Free Will is an Illusion

Francis Crick (1996):
“Your sense of personal
identity and free will are
in fact no more than the
behavior of a vast
assembly of nerve cells
and their associated
molecules.… You’re
nothing but a pack of
neurons.”
Scientists say
Free Will is an Illusion
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Daniel Wegner (2002):
“The fact is, it seems to each of
us that we have conscious will.
It seems we have selves. It
seems we have minds. It seems
we are agents. It seems we
cause what we do…. It is
sobering and ultimately accurate
to call all this an illusion.”

“The brain started first,
followed by the experience of
conscious will, and finally
followed by action.”
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Media spins it for all it’s worth
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Rosen in NYTimes “The Brain on the Stand” (3/11/07): “And
since all behavior is caused by our brains, wouldn’t this
mean all behavior could potentially be excused.”
The Economist (5/23/02): “Potential dystopias always make
good press…. Genetics may yet threaten privacy, kill
autonomy, make society homogenous and gut the concept of
human nature. But neuroscience could do all of these things
first.”
Tom Wolfe in Forbes Magazine (12/2/96):
“the
bottom line of neuroscience … is that, let’s not kid ourselves,
we’re all concatenations of molecules containing DNA, hard
wired into a chemical analogue computer known as the
human brain, which as software has a certain genetic code.
And your idea that you have a soul or even a self, much less
free will, is just an illusion.”
The Problem

Both (some) scientists and science
popularizers rely on implicit
arguments that misconstrue the
relation between neurobiological
discovery and free will.
Argument 1: Conflating
Determinism and Reductionism
1) Determinism means we have no free will.
Many philosophers (like me) deny this claim (and
many folk agree!)
2) Science is showing determinism is true.
No, physics suggests indeterminism is true.
Therefore,
3) Science is showing we have no free will.
Determinism and the
“Horizontal Threat” to Free Will
Past
events
over
which you
have no
control
Long
causal
history,
governed
by laws
of nature
Events
you seem
to control
that
cause
your
decision
Your
decision
Determinism = Every event is completely caused by
prior events, such that given that set of prior causes
(and the laws of nature), the event will definitely occur.
Important distinction: determinism≠ reductionism.
Folk Intuitions about Determinism,
Reductionism, Free Will, Moral Responsibility
80.00
free will
responsibility
Percentage of participant
responses indicating
agreement (somewhat
agree, agree, or strongly
agree) to the questions:
% agree
60.00
40.00
71.21
53.03
20.00
38.89
27.78
0.00
Neuro
Case
Psych
Case
“Ertans are able to make
decisions of their own
free will” (blue bars);
“Ertans should be held
morally responsible for
their decisions”
(green bars).
Folk Intuitions about Determinism,
Reductionism, Free Will, Moral Responsibility
A significant difference
was found when
comparing mean
responses between the
Psych and Neuro cases:
6.00
free will
responsibility
Mean
5.00
Free Will: t(100)=3.29,
p=.001
4.00
3.00
4.27
2.00
3.37
3.70
2.78
** Graphs and Stats by
Trevor Kvaran (B&B Fellow,
Philosophy)
1.00
Neuro
Case
Moral Responsibility:
t(100)=3.33, p=.001
Psych
Case
Determinism is less scary than
Reductionism
Non-reductionistic
description in terms
of psychological
states (desires,
beliefs, plans)
Deterministic
description
RESULTS
Indeterministic
description
PREDICTION
Reductionistic
description in terms
of neural processes
and chemical states
Argument 2: Conflating Free Will
with Cartesian Dualism
1) Free will requires that we have non-
physical (Cartesian) minds that operate
free from the bounds of physical laws.
Why believe this?
2) Science is proving that our behavior is
governed by physical laws.
True that! But this is not new news.
Therefore,
3) Science is proving that we do not have
free will.
The “Vertical Threat” Take 1


Our decisions and actions are entirely caused by
physical events (most proximately, neurobiological
events), leaving no role for the soul (or the
conscious will).
Notice: This physicalist thesis is distinct from the
“horizontal threat” of determinism.
Emergent nonphysical states of
conscious mind
Physical
Causes
Brain Processes
Producing Behavior
Illusory
cause
Behavior
If minds = brains, how can mental
states cause anything?

Last 50 years of philosophy of mind has offered various
theories to explain the metaphysical relationship between
mind and brain:
•
•
•
•

Mind
Mind
Mind
Mind
equal to brain (identity theory)
supervening on brain (supervenience theory)
realized by brain (functionalism)
emerging from brain (emergentism)
Bottom line: The fact that high-level properties are identical
to/supervene upon/realized by ... low-level properties need
not “drain away” the existence of—or the causal powers
of—the high-level properties.
An (overly simple) analogy
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This table is composed of
(realized by) quarks (or
whatever).
The way the quarks are
arranged explain the shape
and solidity of the table.
The shape and solidity of
the table (partially) explain
why I am not falling.
So, do the “high-level”
properties of shape and
solidity cause me not to
fall (or is it just the quarks
that cause it)?
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My mind is composed of
(realized by) neural processes
(or whatever).
The neural processes explain
the (conscious) mental states
I am in.
The (conscious) mental states
I am in (partially) explain why
I do what I do.
So, do my mental states
cause me to do what I do (or
is it just the neural processes
that cause behavior)?
If you answer “neural states,”
watch out for the quarks!
Argument 3: The Real Threat
1) Free will requires that our actions are
governed by our conscious deliberations and
plans in accord with reasons we have
accepted or would accept.
Indeed! Notice this view is consistent with determinism.
2) Science is showing that our actions are not
governed by this sort of rational self-control.
Perhaps. To the extent it is, that is threat to free will.
Therefore,
3) Science is showing we do not have free will.
The Vertical Threat Take 2
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“Modular Epiphenomenalism”: The brain
processes involved in conscious and rational selfcontrol are not involved in most of our decisions
and actions—rather they just create post-hoc
rationalizations for what we do …
Brain Processes
involved in Conscious
Deliberation/Intentions
Physical
Causes
Brain Processes
Producing Behavior
Illusory
cause
Behavior
The Unimportance of
Consciousness?
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David Brooks (NYTimes 9/17/06): “Consciousness has
come to be seen as this relatively weak driver, riding atop
an organ, the brain, it scarcely understands.”
Stephen Morse (in “The Brain on the Stand”): “Suppose
neuroscience could reveal that reason actually plays no role
in determining human behavior … that your intentions and
your reasons are post hoc rationalizations that your brain
generates to explain to you what your brain has already
done” without your conscious participation…. [then]
criminal law would have to abandon its current ideas about
responsibility.
Roger Schank (www.edge.org, 1/5/05): “When people try
to rationally analyze potential options, their unconscious,
emotional thoughts take over and make the choice for
them…. Decisions are made for us by our unconscious, the
conscious [mind] is in charge of making up reasons for
those decisions which sound rational.”
A Possible Reconciliation?
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As long as the relevant conscious mental states
are explained rather than explained away by
neuroscience (and other sciences of the mind),
then free will (the self, morality, etc.) should not
been seen as an illusion. BUT…
The sciences of the mind are discovering and will
inevitably discover certain limitations to the
capacities relevant to free will (e.g., the degree to
which our conscious deliberations influence our
decisions, to which we act on reasons we have
accepted or would accept, etc.)…
So, if mind =
…can we have Free Will?

1.
2.
3.
Yes, I think, but it depends on…
How people understand themselves, free will,
responsibility, morality, etc.
What philosophy has to say about the mindbody relationship, causation, free will,
responsibility, morality, etc.
What the sciences of the mind have to say
about the way the brain (and our psychology)
works.
Libet on the Illusion of Conscious Will
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Subjects asked to flex wrist whenever the feel like it
and to notice the time they are conscious of “urge or
intention” to flex (W)
Readiness Potential (RP) regularly precedes
conscious awareness (W) by about 400ms
-550 ms
RP onset

-150 ms
time W
0 ms
muscle moves
“The brain ‘decides’ to initiate action …before there
is any reportable subjective awareness that such a
decision has taken place.”
Problems with Libet
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Desires (urges) vs. Intentions (or decisions)
-550 ms
-150 ms
RP onset
(urge formed)
time W
muscle moves
(intention formed) (action)


0 ms
Proximate vs. Distal Intentions (planning)
Libet’s task asks subjects to form distal intentions to
flex in response to spontaneously, unconsciously
formed urges to flex
Neuro Case
Directions: You’re going to read a story about another world called Erta that is
very similar to our world. As you are reading it and answering the questions
about it, think of it just as you would any other story you read. Even if you don’t
think that what it says is true in our world, imagine that it is true in Erta.
On Erta, the landscape and life are very similar to Earth, and there are advanced
life forms called Ertans who look, talk, and behave very much like we do. For
instance, the Ertans have families, schools, various jobs, parties, arguments,
etc. However, the Ertans’ science has advanced far beyond ours. Specifically,
Ertan neuroscientists have discovered exactly how Ertans’ brains work. For
instance, they have discovered that whenever an Ertan is trying to decide what
to do, the decision the Ertan ends up making is completely caused by the specific
chemical reactions and neural processes occurring in his or her brain. The
neuroscientists have also discovered that these chemical reactions and neural
processes are completely caused by the Ertan’s current situation and the earlier
events in his or her life. These earlier events were also completely caused by
even earlier events, eventually going all the way back to events that occurred
before the Ertan was born.
So, once specific earlier events have occurred in an Ertan’s life, these events will
definitely cause specific later events to occur. For instance, once specific
chemical reactions and neural processes occur in the Ertan’s brain, they will
definitely cause the Ertan to make the specific decision he or she makes.
Psych Case (differences underlined)
Directions: You’re going to read a story about another world called Erta that is
very similar to our world. As you are reading it and answering the questions
about it, think of it just as you would any other story you read. Even if you don’t
think that what it says is true in our world, imagine that it is true in Erta.
On Erta, the landscape and life are very similar to Earth, and there are advanced
life forms called Ertans who look, talk, and behave very much like we do. For
instance, the Ertans have families, schools, various jobs, parties, arguments,
etc. However, the Ertans’ science has advanced far beyond ours. Specifically,
Ertan psychologists have discovered exactly how Ertans’ minds work. For
instance, they have discovered that whenever an Ertan is trying to decide what
to do, the decision the Ertan ends up making is completely caused by the specific
thoughts, desires, and plans occurring in his or her mind. The psychologists
have also discovered that these thoughts, desires, and plans are completely
caused by the Ertan’s current situation and the earlier events in his or her life.
These earlier events were also completely caused by even earlier events,
eventually going all the way back to events that occurred before the Ertan was
born.
So, once specific earlier events have occurred in an Ertan’s life, these events will
definitely cause specific later events to occur. For instance, once specific
thoughts, desires, and plans occur in the Ertan’s mind, they will definitely cause
the Ertan to make the specific decision he or she makes.
Questions for Participants
1) According to the story, is this statement true or false?
The specific thoughts, desires, and plans occurring in an Ertan’s mind at a
particular time are completely caused by the Ertan’s current situation and earlier
events in the Ertan’s life, and these events were completely caused by even
earlier events, eventually going back to events that occurred before the Ertan
was born.
Based on the story you’ve just read, please write “True” or “False” next to the
following statements to indicate whether you agree or disagree with them:
2) Ertans’ decisions are up to them.
3) Ertans deliberate about what to do.
4) Ertans are able to make decisions of their own free will.
5) Ertans should be held morally responsible for their decisions.
6) If an Ertan does something bad, then he or she deserves to be blamed for it.
7) If an Ertan does something good, then he or she deserves to be praised for it.
8) Ertans are able to lead meaningful lives.
9) Suppose an Ertan named Yon is trying to decide which restaurant to go to for
dinner.
According to the story, is this statement true or false:
Once specific thoughts, desires, and plans occur in Yon’s mind at a particular
time, then there is only one decision Yon can make about which restaurant to go
to for dinner.