Title: The Problem of Free Will
1Metaphysics
2What is freedom?
- surface freedom
- Being able to do what you want
- Being free to act, and choose, as you will
- BUT what if what you will is not under your
control?
- free will
- Being an agent capable of influencing the world
- Source of ones own actions
- Actions and choices are up-to-us
3Why is freedom important?
- We feel that we are free that we are the
originators of our own actions - We need to be free in order to be responsible for
our actions our practices of praise and blame
presuppose that we are free - Greene Paper neuroscience, moral and legal
responsibility, theories of punishment - Roper v. Simmons, 2005, US Supreme Court,
unconstitutional to impose capital punishment for
crimes committed under age 18 - Recent scientific advances in brain research
indicate that the adolescent brain has not yet
fully developed, the decision-making capacity and
risk-taking behavior of adolescents are far
different from those of adults thus adolescent
offenders are less culpable. Roper v. Simmons
The Role of the Science Brief
4Society and free will
- psychological capacities to control our own
lives, change our habits and traits, overcome
addictions, exercise willpower, and consciously
consider the sort of life we want to lead (and to
control our behavior accordingly). - If people interpret free will to include these
sorts of capacities, then telling them that they
dont have free will could have detrimental
effects on their self-conception, interpersonal
relations, and moral behavior, as well as our
political debates and legal practices. It may
make them more fatalistic, less likely to exert
those powers of rational deliberation and
willpower they do have, and less motivated to
improve themselves and their lives Eddy Nahmias
5Principle of alternative possibilities
- In 1969 Harry Frankfurt defined what he called
"The Principle of Alternate Possibilities" or
PAP. - "a person is morally responsible for what he has
done only if he could have done otherwise. - Although I came to class today, I could have
decided not to - What does the world have to be like for this
counterfactual to be true?
6Causal determinism
- (Roughly) the view that the state of the world
at a given time determines the state of the world
at the next moment - Every event that occurs, including human action,
is entirely the result of earlier causes event
causation
7Laplaces demon
- We may regard the present state of the universe
as the effect of its past and the cause of its
future. An intellect which at a certain moment
would know all forces that set nature in motion,
and all positions of all items of which nature is
composed, if this intellect were also vast enough
to submit these data to analysis, it would
embrace in a single formula the movements of the
greatest bodies of the universe and those of the
tiniest atom for such an intellect nothing would
be uncertain and the future just like the past
would be present before its eyes. - Pierre Simon Laplace, A Philosophical Essay on
Probabilities3
8Laplacian Determinism
- O set of physical magnitudes, each of which takes
a determinate value at every moment of time - A history H is a map from R to tuples of values
of the basic magnitudes, where for any t in R the
state H(t) gives a snapshot of behavior of the
basic magnitudes at time t. - The world is Laplacian deterministic with respect
to O just in case for any pair of histories H1,
H2 satisfying the laws of physics, if H1(t)
H2(t) for some t, then H1(t) H2(t) for all t. - John Earman, Aspects of Determinism in Modern
Physics
9 Neuroscientists Complete Fully Mechanistic
Explanation of Human Behavior
- These neuroscientists have shown that once
specific chemical reactions and neural processes
occur in a persons brain, they will inevitably
cause the person to make the specific decision he
or she makes. - As noted scholar Francis Crick says, 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.
Youre nothing but a pack of neurons. Said Paul
Katz, one of the lead researchers, There is
certainly no room left for a soul now. There is
nothing left for a soul to explain.
February 20, 2049 By Eddy Nahmias Neuroscientists
at the University of Chicago and Georgia State
University have found evidence that explains
exactly how all human decisions and actions are
entirely caused by neurobiological activity. They
report that whenever we are trying to decide what
to do, the decision we end up making is
completely caused by the specific chemical
reactions and neural processes occurring in our
brains.
10Determinism types
- Causal determinism
- Theological determinism
- Psychological determinism
- Sociological determinism
- Biological determinism
- Environmental determinism
11Compatibility?
- This raises two big questions
- The determinist question - is determinism true or
false? - The compatibility question - is free will
compatible with determinism? - The combination of answers that can be given form
the standard positions in the debate
12Positions in the Free Will DebateDiagram taken
from http//en.wikipedia.org/wiki/Free_will
13Incompatibilism
- Incompatibilists believe freedom is not
compatible with determinism if determinism is
true, then one cannot be held truly free and
responsible for ones actions - Incompatibilists may be divided into two groups
14Incompatibilism Hard Determinism
- Free will is not compatible with determinism
- Determinism is true
- So, we do not have free will
- HARD DETERMINISTS are incompatibilists who hold
that determinism is true
15Incompatibilism libertarianism
- Libertarians believe
- We do have free will
- Free will is not compatible with determinism
- Determinism is therefore false
16Compatibilism
- COMPATIBILISTS believe that freedom and
responsibility are in every significant sense
compatible with determinism thus there is no
conflict between determinism and free will - SOFT DETERMINISTS are compatibilists who believe
determinism is true - Classical Compatibilists Hobbes, Hume, Mill
- Modern Compatibilists Ayer, Dennett, Frankfurt
17Hard Determinism
- Free will is not compatible with determinism
- Determinism is true
- Therefore, free will is an illusion
- Support?
18Hard Determinism
- CONSEQUENCE ARGUMENT (informal)
- If determinism is true, then our acts are the
consequences of the laws of nature and events in
the remote past. But it is not up to us what went
on before we were born, and neither is it up to
us what the laws of nature are. Therefore the
consequences of these things (including our
present acts) are not up to us. - Peter van Inwagen, An Essay on Free Will (p. 56)
19Hard Determinism
- Problems
- How can the HD explain our behaviour of praising
and blaming agents for their actions, and
ascribing responsibility? - What happens to morality? If nobody can ever do
otherwise than they in fact do, then notions of
responsibility, desert, praise, and blame are
redundant.
20Soft Determinism (compatibilism)
- Determinism is true
- Free will exists
- There is no tension between these claims
- If some people see a tension here, it is because
they are misunderstanding the notions of freedom
and determinism, of free-choice and causal
necessity
21Challenge for the compatibilist
- Incompatibilists say
- For our actions to be free, it must be the case
that, when we act, we could do otherwise than we
actually do - This insistence on the ability to do otherwise is
often referred to as the principle of alternate
possibilities
22Compatibilist responses
- Interpret the CDO-condition of freedom as having
a hypothetical or conditional meaning, i.e. - To say one could have done otherwise is to say
that one would have done otherwise had things
been different (given a different set of beliefs,
desires, etc.) - classical compatibilist response
23Compatibilist responses
- So what if I couldnt do otherwise?
- The ability to do otherwise is not in fact
required for moral responsibility, and so
determinism is no threat to free will - The proper contrast to freedom is not
determinism, but constraint/coercion - As long as we are not constrained, coerced or
forced in our actions then we do what we will,
and it doesnt matter whether our wills are
determined or not
24Frankfurt
- Donald is a Democrat and is likely to vote for
the Democrats in fact, only in one particular
circumstance will he not that is, if he thinks
about the prospects of immediate American defeat
in Iraq just prior to voting. Ms White, a
representative of the Democratic Party, wants to
ensure that Donald votes Democratic, so she
secretly plants a device in Donald's head that,
if activated, will force him to vote Democratic.
Not wishing to reveal her presence unnecessarily,
Ms White plans to activate the device only if
Donald thinks about the Iraq War prior to voting.
As things happen, Donald does not think about
Iraq prior to voting, so Ms White thus sees no
reason to activate the device, and Donald votes
Democratic of his own accord. Apparently, Donald
is responsible for voting Democratic although,
owing to Ms. White's device, he lacks freedom to
do otherwise.
25Compatibilism problems
- compatibilist freedom is only surface freedom -
it is not free will in the full, proper sense - Compatibilism is a wretched subterfuge (Kant),
a quagmire of evasion (William James)
26Libertarian (free will) position
- Libertarians believe
- Free will is not compatible with determinism
- Free will exists
- Determinism is therefore false
- Support?
- Criticism?
27Does indeterminism help?
- Would you be willing to spend a day letting
randomness govern your actions?
28Libertarian (free will) position
- More serious problem
- If determinism is false, then events are not
subject to chain of cause-and-effect - So events occur randomly, by chance
(indeterminism) - If events occur by chance, then they are not
under our control - So, how can we be free and responsible?
29Libertarian (free will) position
- This is known as the Intelligibility Question -
how do we make sense of a non-determined free
will? - 3 common responses
- Agent-causal theory (self-determination)
- Simple indeterminism
- Causal indeterminism
30Agent causation
- Not only events can be causes agents themselves
can be causes too (distinction between
event-causation and agent-causation) - Agent-causation is not reducible to causation by
events (agent-causes are not explainable by
reference to other events) - A STAFF MOVES A STONE, AND IS MOVED BY A HAND,
WHICH IS MOVED BY A MAN - Aristotle, Physics 256a
31Agent causation
- Problems
- Many people, including many libertarians, find
the notion of agent-causation far too
mysterious and problematic - Requires agents to be the uncaused cause of their
actions, to be prime movers unmoved - Problem of economy - positing a second,
additional, category of causation
32 1. Is Determinism true? 2. Can there be Free
Will?
- Determinists
- 1. YES
- 2. Depends
- Compatibilists (Soft Determinists)
- 2. YES
- Hard Determinists
- 2. NO
- Libertarians
- 1. NO (since FW exists)
- 2. YES