“Determinism” defined: Every event has a cause/set of causes; if its cause occurs, then the
effect must follow.
In the assigned reading by David Hume, Hume calls determinism the “principle of
necessity” and claims that a belief in its truth is part of common sense. To give an example
(mine, not his): when someone in the 20’s suddenly falls dead, we don’t think “well,
sometimes things like that just happen.” We think that the person’s death must have had a
cause. If the coroner is unable to identify the cause, we don’t think that this is an uncaused
death. Instead, we think that there must have been a cause, even if we can’t identify it.
According to determinism, our inability to make accurate predictions about some natural
events (e.g. Will the hurricane now of the coast of Florida touch land, and if so where?
What number will appear on the dice, on this craps player’s next throw?) is due to our
ignorance of the laws of nature and the causes that are in play. An hypothetical omniscient
scientist who knew exactly what state a system is currently in, what “inputs” it is receiving,
and what laws govern that system’s behavior, would be able accurately to predict that
system’s future states. This holds for hurricanes, people, the solar system, and everything
else in the universe.
If determinism is true, then it follows that all of the choices that we make have causes;
given those causes, we have to make the particular choices that we do.
Determinism holds that just as a computer’s “outputs” are caused by its “inputs” and the
software that it’s running, so too, every choice that we human beings make is caused by
inputs we receive from the present environment and the beliefs, desires, and other
psychological traits that we have. The difference between computers and people is that
computers are much simpler, better understood, and so, predictable, whereas humans are
more complex, not so well understood, and thus, less predictable. The reason why the
choices of most people are hard to predict accurately is not that their choices are uncaused,
but rather, that the causes are very complex.
-data or info. being received
from the current environment
(“sensory inputs”)
-genes
+
 -decision to
+
 -beliefs, desires &
do x, not y or z.
-upbringing,
other psych. traits
(“the outputs”)
socialization,
(“the brain’s software”)
learning
-- Determinists can disagree about how important socialization is vs. how important
biology/genes are. They can hold polar opposite views in the "nurture vs. nature" debate.
For example: why are men more violent than women? In every known society, past
and present, over 90% of all violent crimes are committed by males. Perhaps the
explanation has to do with the differences between male and female brains ("nature"). Or
perhaps the explanation is that in all societies men are taught to be "macho" and women to
be "feminine" ("nurture"), and macho upbringing leads to more violence than feminine
upbringing. Either explanation is compatible with determinism.
The definition of determinism does not say or imply either that we do or that we don’t have
free will. Whether or not free will is compatible with determinism being true can’t be
established just by examining that definition. One must also understand what is the correct
definition of “free will.” (Of course, there’s disagreement about what is the correct
definition).
-- Determinism differs from fatalism. Determinism says that the past determines the
present and the present determines the future. Fatalism says that the future is cast in stone,
or that many of the most important things that will happen to us tomorrow will happen no
matter what we do today.
1
the past
2
the choices we make
in the present
3
what happens to us
in the future
Fatalism says that 3 is fixed, that changing 2 won’t make any difference to 3.
For example, fatalism says that the grade you will get on your next exam on this class is
fixed, so it doesn’t matter whether you do the assigned reading and attend lecture between
now and exam time or not. Determinism (and common sense) say otherwise. If you study
hard, that’s likely to cause a higher grade; if you blow off studying, that’s likely to cause a
poor performance and a lower grade. Of course determinism implies that your decision to
study hard or blow it off has causes in your genetics and socialization, and given those
causes, you have to make the decision that you do.
In order to determine whether or not free will is real, we have to know what the definition
of it is (otherwise we won’t know what to look for). So what is the definition of free
will?
Here are some “commonsense” points about what “free will” isn’t and about who doesn’t
have it. A satisfactory “theory” or “definition” of “free will” must be consistent with all
of these points:
1. We don’t think that fish or even dogs have it. (That’s why many would agree that a
dog should be put down if it’s dangerous, but few would say that it should be put down
because it’s evil. Moral evil requires the capacity for free will, which dogs lack). But
neither does it seem that free will is something that only humans could possibly have. If
there are Vulcans (from the Star Trek TV series) on a faraway planet, they would not be
homo sapiens, but they would have free will.
2. We don’t think that all humans have it. Not the “brainwashed,” the severely mentally
retarded, the seriously mentally ill, or infants and very young children.
3. Free will is not to be identified with the ability to make choices, or the exercise of that
ability. The ability to choose, and the exercise of that ability, is necessary but not
sufficient for free will. It makes perfectly good sense to say that someone chose to do x,
but lacked free will in making the choice. A brainwashed person might choose to try to
assassinate the President, but if that choice is due to his having been brainwashed (via
chemical injections, electric shocks, etc.), it is not the result of free will.
4. Free will is not indestructible. If someone has free will, he can lose it, either
temporarily or permanently, via the ingestion of certain drugs (e.g. ones that cause
psychotic delusions), severe mental illness, lobotomy, etc.
5. Free will is not to be confused with freedom. Being free is a matter of having lots of
opportunities. If you’re put in a prison cell, your options or opportunities are drastically
reduced, and thus, your freedom is reduced. But your free will is unaffected. Free will
(assuming it exists) seems to be a matter of having certain mental capacities—including
the capacity to weigh the pro’s and con’s of different options, and choose accordingly. It
may be more than that, but it’s at least that.
A menu of possible positions on free Will, determinism, and their relationship
Let D stand for the statement “determinism is true.” Let F stand for the
statement “at least some of our choices we make of our own free will.” We
can now distinguish some of the different positions in this debate as follows.
Compatibilism: D and F are compatible. That is, it is possible for both
statements to be true simultaneously. (The relation between D and F is
analogous to that between wearing a green shirt and wearing a striped shirt—
it’s possible to do both).
Incompatibilism: D and F are incompatible. It is impossible for both to be
true. If one is true, then the other has to be false. (The relation between D
and F is analogous to that between living in Arizona and living in
Afghanistan—it’s impossible to do both at the same time).
Incompatibilism can be defined in terms of an if-then statement, namely:
If D, then not F. or
If F, then not D.
(These two conditional statements are equivalent; they’re “contrapositives.”
See p. 14 of our textbook).
Libertarianism says:
If F, then not D. (Incompatibilism)
F
---------not D.
Hard determinism says:
If D, then not F. (Incompatibilism)
D
---------not F.
Soft determinism says:
D
F
---------D&F
---------It’s possible that (D & F) (Compatibilism)