I am lecturing on free will
this week. This is one topic that is
logically well organized in the history of modern philosophy. There are two fundamental questions: are
human choices determined by the past, and can human beings be morally
responsible for their choices? These
give rise to four possible positions.
Hard
Determinism. This
position may be described by the following argument:
1. If human choices are determined by the state of the Kosmos (D) prior to those choices, then free will is impossible (~F).2. D.3. Therefore: ~F.
That is a straight forward
modus ponens argument, and so it is valid.
If you do not want to accept the conclusion, then you have to reject one
of the two premises. Here F can be
understood as metaphysical freedom (uncaused action) or moral freedom (an
action for which the actor is morally responsible). The hard determinist rejects both kinds of
freedom.
The strength of this view is
that it preserves the principle of the uniformity of nature, if that principle
implies determinism as many thinkers suppose.
Libertarianism. This position may be defined by a modus tollens
which begins with the same premise:
1. If human choices are determined by the state of the Kosmos (D) prior to those choices, then free will is impossible (~F).2. F.3. Therefore: ~D.
Again, this is a valid
argument. As hard determinists boldly
state D, libertarians boldly state F.
Libertarians conclude that determinism is false, at least as applied to
human beings, who they believe to be agents capable of uncaused action.
The strength of libertarianism
is that it preserves our common sense experience of choosing. My sense of having choices is as vivid as my
sense that the world is solid underneath my feet.
Because they share premise 1,
the two positions are both called incompatibilist. Hard Determinism and Libertarianism both
regard determinism and free will to be incompatible.
Compatibilism. The third view, perhaps the dominate one in
philosophy, rejects premise 1 above and may be expressed in a simpler
argument.
1. F and D.2. Therefore F.3. Therefore D.
Again that is valid, if
tautological. Compatibilists believe that
free will is not only logically compatible with determinism, but that it
actually requires it. Why do we praise a
person as good because of her good actions if not because her good character
determined those actions? It is likewise
with blameworthy actions.
Compatibilists think that hard
determinists and libertarians are focusing on the wrong things. Am I free to leave the room I am sitting
in? To answer that question we don’t
need to ask whether my decision to leave is determined by the state of the
cells in my brain prior to my decision.
We need to ask whether the door is locked or not, or whether I know that
someone is waiting outside to do me harm.
Human actions are free, in this
view, if at least two conditions are met:
1. The agent is not compelled to act or not act (either by physical constraints or compelling threats) and2. If the agent had acted otherwise, she would have done otherwise.
I suspect that condition one is
contained in condition two. The question
is not whether my choices are caused
by prior states of the Kosmos (they are, according to the compatibilist) but
whether my choices are causes of my
actions. To the extent that the latter
is true, I am free.
The strength of Compatibilism is
that it saves moral responsibility by immunizing the same against determinism. Why do we seem largely agree to hold sane
people responsible for the crimes that they commit while holding that insane
people are not responsible? This is
because sane people respond in more or less predictable ways to moral
sanctions. They understand that they
will be punished for infractions and so are less likely to commit them. Insane people are incapable of a rational
response to such sanctions. Precisely
because sane people are more or less responsive to legal sanctions (along with
moral opprobrium) such moral sanctions make sense. There is no point in applying them to a full
tilt loon.
It occurs to me, however, that
there is a fourth position. This is in
fact my position. This position is
compatibilist in so far as it denies that determinism and free will are
incompatible. I think that what matters
is that my choice determine my action, regardless of whether my choice is
determined by the past. In that respect,
I agree with the compatibilists.
However, I don’t see any reason
to accept determinism. No reasonable
person would deny that the past influences the future. If yesterday you offered me a lot of money to
write an essay, I am more likely to write it today. However, influenced and determined are never
the same. If X influences Y in a very
robust way, then Y is predictable from X.
That is the kind of relationship that science mines. It is enough to calculate the influence. Does X result in Y 99% of the time? That is a robust finding. Science rarely if ever gets to %100. All or almost all science is probabilistic rather
than determinist.
It is common to assume that
this is because of limits on the data or apparatus. We can only measure anything to within some
margin of error. But why assume that? The assumption is unnecessary. This state of X makes the subsequent state of
X more or less probable. That is the
best we can ever do.
Determinism is one of the great
myths of modern science. It is an
attractive idea, useful to some degree in thought, and altogether unfounded in
reality.