determinism and free will. freedom a preliminary definition of freedom: ‘to be free’ = ‘to be...

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Determinism and Free Will

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Determinism and Free Will

Freedom

A preliminary definition of freedom:

‘to be free’ =

‘to be able to choose one course of action instead of another’

Free? Consider Faten Khorshid

here. She seems able ‘to choose differently’: she could leave Saudi Arabia, after all.

Mashael al-Eissa (20-something blogger): “Saudi women are the luckiest in the world.”

Samia Adham, a statistics professor: “This is a choice. We choose to be ruled by Islam.”

Are these free choices?

Cultural determinism

We may be practically free to choose, but our choices could follow cultural or social forces beyond our control.

For example: if religious beliefs are freely chosen, then religious beliefs should be evenly distributed around the world. But they aren’t: religions cluster by geography and culture. (Very few Saudis ‘choose’ to be Christian, for example.)

The plausibility of determinism

The shoe fits us, too. If you weren’t born into the family you were, would you like the sports you like? Follow the religion you do? Have the political views you do? Have the interests you do? We aren’t different from Ms. Korshid.

Defining ‘determined’

An event is determined when there are earlier conditions whose occurrence is a sufficient condition for that event happening.

That is, the event is bound to happen, if these conditions occur.

E.g.: You drive a car 90 mph into a wall. There’s no room for “free will” here. No

matter how hard you “choose”, given that condition, the outcome is determined.

Determinism (definition) All events are caused by past events such that,

given a set of past events, the future could not happen in any other way. That is, given its initial conditions and the laws of nature, the universe has only one physically possible future.

So: for any person, given past events in her life (from genes, upbringing, environment, how she feels, accidents, etc.), her life could not have turned out any other way: she was going to choose Islam, like chocolate, etc.

Some varieties of determinism A simplified version of determinism is part of

common sense: everything that happens has some sort of cause.

Note that determinism doesn’t specify what sorts of causes these are: they could be physical, genetic, neurological, psychological, social, cultural, theological, etc.

We are all closet determinists Suppose you were dating someone and they

broke up with you, and they said: “No reason, no cause. Just free will.” You wouldn’t believe it! Or if: Your boss fired you. Your car broke down.

In these cases, you’d think there was a reason or a cause that made it happen. You’re being a determinist!

Two conflicting intuitions

Common sense pulls us in two directions: Every event is deterministically caused. Choices

happen the way they do because of causes and reasons that determine them. The future is determined consequence of the past.

We are usually free to choose, and the outcome of such choices is “up to us”. Things could have turned out otherwise than we in fact chose. The future is open.

Different arguments for determinism If God exists, determinism is plausible. Everything we know about nature at a non-

quantum level follows deterministic laws. Lots of evidence in psychology and neurology

suggests we choose due to causes such as genes, environment, and neurology.

Everyday common sense usually makes determinist assumptions about character, behavior, and causes.

Theological determinism

1. If God exists, then God knows the future.

2. If God knows the future, then the future is fixed.

3. If the future is fixed, then we can’t choose to do anything other than what we do.

4. If we can’t choose to do anything other than what we do, then we have no free will.

5. So: if God exists, then we have no free will.

Genes and complex behavior: animals Cuckoo chicks push other eggs out of the

nests they’re in, and imitate the birds they are displacing.

Spiders build and repair webs from birth. Both of these (and many other complex

behaviors) occur without learning. Identical twins have strongly similar

personality traits.

Psychological examples of humans determined by their environment People who have just found money on the

ground are 22 times more likely to help someone who drops papers than people who have not found money (88% vs. 4%).

A power lawnmower makes people less willing to help (80% vs. 15%).

Random subjects told to hurry mostly don’t help injured people asking for help, but people told there is no hurry often do (10% vs. 63%).

Neurological examples of determinism Damage to the insular cortex of the brain

makes nicotine addiction vanish. (It also causes loss of interest in orgasm, loss of emotional response to music, and the inability to distinguish fresh from rotten food.)

Gradual electrical stimulation of the parietal cortex triggers at first wanting to roll the tongue, and eventually rolling the tongue.

Benjamin Libet’s experiment

What would determinism imply?If determinism is true, does that mean we have no free will?Yes, determinism is true, and so we have no free will. (Hard Determinism)Yes, but we have free will, so determinism is false. (Libertarianism)No, determinism is true, but we have free will. (Compatibilism)

Compatibilism

Compatibilists claim that our two basic intuitions are both correct: that everything is determined by causes, and that we have free will.

How?

Compatibilism

The compatibilist agrees that we have the ordinary, everyday experience of wanting to do something, and then doing it, and that these are real choices, and are unforced.

However, the compatibilist also agrees that everything that happens has a determinate cause.

So even our choices, free and unforced as they are, are determined.

Compatibilism

The compatibilist thinks determinism sounds scary because we confuse it with misleading metaphors. We think it is like: Being in prison Someone controlling us Being a robot following a program Having a fate that robs us of all initiative

The compatibilist says these are false ways of understanding determinism.

Compatibilism

The compatibilist says we make choices, and that many of those choices are free.

The compatibilist says what we mean by “free choice” is not “undetermined by past events.”

What we mean by “free” is “doing what we want; not being forced by external circumstances to do something we don’t want.”

“Unconstrained” ≠ “uncaused”

Compatibilism

Causes don’t constrain our actions, like a jail or someone controlling us would. Causes are not outside us, stopping us, but are part of us, enabling us to act. (Do legs constrain jumping? No, they enable it.)

Natural laws aren’t agents, so they aren’t programming us like robots. Gravity, e.g., isn’t a puppeteer. We deliberate and choose within natural laws, as we are part of nature.

Determinism isn’t fatalism, either.

Determinism ≠ Fatalism

Fatalism is the view that the future is fixed, no matter what the past or present is.

Determinism is the view that the future is fixed by what the past and present is.

Determinism implies our actions make a difference and change the future, whereas fatalism says our actions don’t matter.

Compatibilism on choosing otherwise What about ‘choosing something else’? Isn’t

that needed for free will? To say I ‘could have done otherwise’ is to say

that I would have done otherwise if things were different (given a different set of beliefs, desires, etc., or if I had been in a different situation, with different causes acting on me).

“I would have chosen mint if I had wanted to.” This is called the conditional analysis of

“could have done otherwise.”

Harry Frankfurt’s compatibilist critique of alternative possibilitiesFrankfurt (b. 1929) imagines a situation where you can’t choose otherwise, because a master manipulator would push you into doing the action regardless. But if you choose that action, it was free (your desire), and you are still responsible for it, even if you couldn’t have avoided doing it because of the master manipulator. So Frankfurt concludes that “being able to choose otherwise” isn’t necessary to have freedom or responsibility.

Compatibilism

For the compatibilist, to be a free choice, it is enough that our choices are caused by our own desires and beliefs, rather than any external forces beyond our control.

However, this raises a hard problem for the compatibilist: where do our desires and beliefs come from, originally?

The Consequence Argument (An argument for incompatibilism) You do what you do because of the way you are. To be responsible for what you do, you must be

responsible for the way you are. But to be responsible for the way you are, you

must have done things to make you the way you are.

To do things to make you the way you are, you must have been responsible for the way you were then.

And so on….

The Consequence Argument

“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 those things (including our present acts) are not up to us.” (Peter van Inwagen, b. 1942)

Hard determinism

Since our original natures are beyond our control (from birth, or our early childhood), we cannot be responsible for who we become later.

If the compatibilist thinks unfree actions come from external causes beyond our control, then all our actions are originally caused by unfree causes. So, no choices are free.

Hard determinism

According to the hard determinist, there are no free choices: the unforced ones are as beyond our control as the forced ones.

So our ideas of praise and blame are inconsistent: we don’t blame or praise people for their height, e.g., but we often do blame for weight, intelligence, criminality, etc.

Punishment wouldn’t be based on deserving it, but on changing behavior.

Libertarianism

The libertarian argues that free will is real and non-deterministic: that at least some human choices could have occurred otherwise than they did, given the exact same causes.

Common arguments for libertarian free will include: Our feeling of freedom The need for moral responsibility The indeterminist nature of quantum physics

Three main types of libertarianism Non-causal (simple indeterminism): free

acts are uncaused basic mental actions. Agent-causal: free acts are caused by an

uncaused substance (a “person” or “agent”).

Event-causal: free acts are caused by undetermined events in the brain.

Agent-causal libertarianism

If you deny that “undetermined = random,” and think that YOU just choose without any prior causes, then you may agree with agent causation.

On this view, our choices are neither determined nor random, but choices caused by ourselves. We are each a personal self, a substance or agency outside of causal determination. We cause our choices.

Criticism of agent-causation: It’s magic Everything else in the universe (except perhaps

quantum phenomena) has causes. The agent causation theory claims persons are somehow different from everything else.

This contradicts scientific theories of human biology, psychology, and common sense.

Why not animals? Agents aren’t events, nor are their choices

caused by events. So why do we make decisions at particular times?

Simple indeterminism: non-causal mental acts When we act freely, there are uncaused,

basic mental actions: willing, choosing, etc. They have an “actish phenomenal quality”

(Carl Ginet): it feels like I am making something happen.

But in truth, these basic mental acts are not caused by anything at all (that’s how they can be undetermined).

Criticism of non-causal willing: It’s unclear how we’d control choices

Since it’s not random, I chose from reasons. But how do reasons affect my choices without any causation?

Either my reasons for acting are (a) due to causes outside me, or (b) I chose which reasons to act on.

But if (a), then it’s a form of determinism. If (b), then my choice of reasons either had

reasons or it was uncaused. But then, that’s either an infinite regress or randomness.

A problem for libertarians: luck If determinism is false, then some events are

not subject to cause and effect. If so, then some events just happen, without

determining causes. (Indeterminism) They would be random events. But events that just happen aren’t under our

control, in which case we are not responsible for them.

My choices would be a matter of luck.

Kane’s event-causal libertarianism Some choices are caused by physically

undetermined processes in the brain. In these chaotic events, we feel torn between

different possible futures. That is because parallel processes in the

brain are competing with each other. Our choices are caused by undetermined

events, but both possibilities are ours, so there is non-random responsibility either way.

Criticism of event-causation

The event-causal hypothesis needs specific physical-biological processes: Choices need to cause chaotic brain states. These brain states need to be affected by

quantum indeterminacies. The quantum indeterminacies need to be

amplified by the brain states in a way that tips choices one way or another.

But there is no empirical evidence that any of these actually happen.

Hard Incompatibilism: free will is incompatible with both determinism & indeterminismIf determinism is true, does that mean we have no free will?Yes, determinism is true, and we have no free will. (Hard Determinism)Yes, but we have free will, so determinism is false. (Libertarianism)No, determinism is true, but we have free will. (Compatibilism)Yes, but even if determinism is false, we still have no free will. (Hard Incompatibilism)

The hard incompatibilist’s dilemma

1. Determinism is either true or false.

2. If determinism is true, then no one can never choose other than what they were going to.

3. If no one can never choose other than what they were going to, no one has free will.

4. So: if determinism is true, no one has free will.

5. If determinism is false, then some events are random.

6. If you do something random, it is not your choice.

7. If an act is not your choice, it is not free will.

8. So: if determinism is false, acts aren’t from free will.

9. So: either way, there is no free will.

No free will There is free will

Determinism is true

Hard Determinism

Compatibilism

Determinism is false

Hard Incompatibilism

Libertarianism

We feel ‘free’, but …

Let us imagine a man who, while standing on the street, would say to himself: ‘It is six o’clock in the evening, the working day is over. Now I can go for a walk, or I can go to the club; I can also climb up the tower to see the sun set; I can go to the theatre; I can visit this friend or that one; indeed, I also can run out of the gate, into the wide world and never return. All this is strictly up to me; in this I have complete freedom. But still, I shall do none of these things now, but with just as free a will I shall go home to my wife.’ This is exactly as if water spoke to itself: ‘I can make high waves (yes! in the sea during a storm), I can rush down hill (yes! in the river bed), I can plunge down foaming and gushing (yes! in the fountain) I can, finally, boil away and disappear (yes! at certain temperature); but I am doing none of these things now, and am voluntarily remaining quiet and clear in the reflecting pond. [Schopenhauer, 1839]

Benjamin Libet’s experiment (1985) Voluntary movement is preceded by

“readiness potential” (RP): a negative shift in electrical potential in the brain that can be measured by electrodes on the scalp.

Libet theorized: If conscious intention is what causes movement, then the subjective feeling of choosing should come before the physical actions of moving, such as the RP.

So he timed all three: choice, RP, movement.

Libet’s methodology

Timing the movement was done with electrodes on the appropriate muscles.

Timing the RP was done with electrodes on the scalp, measuring activity in the motor cortex of the brain.

Timing the choice (Libet called this “W”, for “will”) was done by having the subjects watch a rapidly spinning ‘second hand’ on a clock-like monitor, and asking them to say exactly where the dot was at the moment they chose to move their arm.

Libet’s results

The RP came first, at an average of 550 ms (a little more than half a second) before the action.

The W occurred, on average, 200 ms before the action.

These results held true regardless of whether the act was preplanned or ‘spontaneous’, and were repeated using different ways of measuring both RP and W.

Our felt choices happen after our brains act.

Determinism and free will: Conclusions Determinism is plausible. We base much of

our lives on determinist assumptions. Aside from quantum physics, determinism is well-supported. In the biology, it is plausible.

The case for free will is based on intuitions, and “it might possibly be” theories being true in just the right way to fit intuition. Intuitions are not very reliable.

(59% of philosophers are compatibilists, 14% libertarians, 12% hard determinists, 15% “other.”)