Transcript Smith’s Invisible Hand

The Problem of
Free Will
Introduction to Philosophy
Jason M. Chang
Lecture outline
1.
Why care about free will?
2.
The problem of free will
3.
Causal determinism
4.
Is human action causally determined?
5.
Objection to determinism
Why care about free will?
Joe is standing on top of a 3-story
building. Suddenly, a strong gust of
wind blows, causing Joe to lose his
balance.
Joe falls off the building and lands on
a pedestrian below, thereby killing the
pedestrian. Joe, however,
miraculously survives.
Should we blame and punish Joe for killing the pedestrian?
Note: This example was created by Dr. Garret Merriam.
Why care about free will?
Mo is standing on top of a 3-story
building. Mo falls off the building
and lands on a pedestrian below,
thereby killing the pedestrian.
It turns out that Mo chose to fall off
the building with the intention of
killing the pedestrian.
Should we blame and punish Mo for killing the pedestrian?
Note: This example was created by Dr. Garret Merriam.
Why care about free will?
Why the different reactions toward Joe verses Mo?
o
o
Mo had free will
Joe did not have free will
Blaming or punishing someone requires that they had free will
Why care about free will?
Punishing someone requires that they
had free will
•
How this plays out in the legal system
o
Different degrees of criminal
homicide
o
Diminished capacity and
insanity defense
Question
Do we have free will?
Commonsense answer
Of course we have
free will!
The problem of free will
The problem of free will
Ancient and Medieval version of the problem
(1) We have free will!
(2) God is all-knowing!
The problem of free will
Modern version of the problem
(1) We have free will!
(2) Modern science
How does modern science conflict with free will?
Causal determinism
Imagine an apple falling from the tree.
How do we explain the motion
of this object?
The motion of all physical objects in the
universe (apples, stars, planets, liquids,
gases, light, energy, etc.) can be explained
in terms of scientific laws.
Causal determinism
Scientific
worldview
Support
Causal
determinism
Causal determinism = the view that all events of physical objects
in motion are the inevitable consequence of both prior events
and scientific laws
Causal determinism
Example of causal determinism
Imagine an event in which a single
domino (D4) falls in a “domino
effect” series.
How did the event come about?
D4
Causal determinism
Prior events
Scientific laws
(prior dominos
falling, me tipping
the first domino,
etc.)
(law of gravity, laws of
thermodynamics, etc.)
Event – some
domino (D4) falls
Determinism  All events in the universe are like this.
Causal determinism
Oct. 17, 1989,
5:04pm in San
Francisco
BIG
BANG
Present day
Big chain of cause and effect
Causal determinism
La Place’s demon
Imagine that determinism is true.
Also imagine that a Being (a Demon)
knows the precise location and
momentum of every atom in the
universe and all the laws of science.
What, in theory, could this Being do?
Pierre-Simon La Place (1749-1827)
Is human action causally determined?
Is human action causally determined?
From the standpoint physics and chemistry
99.9999% of
matter in the
universe is
governed by
causal laws
Humans are
composed of matter
-Oxygen (65%)
-Carbon (18%)
-Hydrogen (10%)
-Nitrogen (3%)
Humans are no exception
Is human action causally determined?
From the standpoint biology and social science
Genes
Environment
Is human action causally determined?
From the standpoint biology and social science
Imagine someone who knows you so well
that they can predict what you will do or say
in most given situations.
Is human action causally determined?
From the standpoint biology and social science
Imagine a person that has complete
knowledge of our genes, our past
experiences, and the environment in which
we grew up.
It is likely that this person can predict with
100 percent accuracy what we will do or say
in a given situation.
Is human action causally determined?
100 %
Prediction
accuracy
Knowledge of genes,
past experiences, and
environment
Complete
knowledge
Is human action causally determined?
Definition of causal
determinism
The view that all
events (including
human action) are
the inevitable
consequence of both
prior causes and
scientific laws
What this means
Humans cannot do
otherwise
Prior causes don’t just influence
but determine behavior
Objection to
determinism
Objection to determinism
The objection:
I feel free, so determinism is
obviously false!
Objection to determinism
Have you ever done something but
were unaware of all the factors that
made you do it ?
Poll: Are we ________ aware of
all the factors causing our
decision?
(1) always
(2) sometimes
(3) never
Objection to determinism
Biological
make-up
Past
experiences
(millions)
Current
situation
(millions)
There are millions of factors that cause a decision
Most of these factors we are ignorant of
Misconceptions about determinism
“It is the great complication of motion in
man […] it is the multiplicity of causes that
move him […] that persuades him he is a
free agent; if all his motions were simple
[…] he would perceive all his actions were
necessary […]”
Baron D’Holbach (1723-1789)
Misconceptions about determinism
Knowledge
of our
causal story
Our confidence that we can do
other than we do is inversely
related to knowledge of our
causal story (i.e., the millions
of causes that move us)
Confidence we can do
otherwise
Summing up
•
Free will is required for moral responsibility
•
Belief in free will conflicts with scientific beliefs
•
Science seems to support causal determinism
•
Causal determinism is the view that all events are the
consequence of previous events and scientific laws
How can we reconcile contemporary scientific worldview
with free will and moral responsibility?