David Hume’s Compatibilism“It was David Hume's remark that first, many years ago, interrupted my dogmatic slumber and gave a completely different direction to my enquiries in the field of speculative philosophy.”

- Immanuel Kant

Three Views of The Will• Libertarianism – the agent has more than one option open to her and

could have chosen otherwise than she actually chose. The libertarian believes that the movement of the will is uncaused but also not random. Choices are solely and fundamentally the agent’s own choices. An agent’s choice of what they want is not a necessary one, and the responsibility for her choice lies solely with her.

• Compatibilism - the agent only has one option open to her, but she still chooses the action that she wants to choose. The compabilist believes that the movement of the will is caused by factors external to it (such as one’s character, values, environment, etc.). An agent’s choice of what they want is determined by her desire (external to the will) but is also free because she does what she wants. Because of the latter, agents are responsible.

• Determinism – the agent has only one option open to her; thus, she is not free because freedom requires the ability to choose otherwise than she actually chose. The determinist believes that the movement of the will is influenced by external factors of biology, genetics, etc. Every event has some cause or other, so an agent’s choice is thus determined by some antecedent event or other. An agent’s choice is a necessary one. Many determinists deny moral responsibility.

Cause and Effect: Necessary Connection?

According to Hume, the concept of cause and effect is NOT a priori, or necessary. It cannot be discovered by reason alone without the aide of experience. Rather, cause and effect is simply a posteriori knowledge of two objects constantly conjoined (always occurring one after the other).

Imagine an alien encountering water for the very first time. It could not infer by reason alone, simply based on the properties of the water, that it could drown someone. For Hume, causes never reveal their effects to the rational faculties alone. Only experience can teach us effects.

It seems easy to grant Hume’s point regarding objects that were formerly unknown to us, very uncommon objects and effects dependant upon an intricate series of causes; however, what about objects we have always known, new objects that are familiar to others we encounter and effects dependant upon some easily observable property of a cause? In these later instances, can we discover the concept of cause and effect in those objects by reason alone.

Imagine you have absolutely zero knowledge of physics. You walk up to a billiard table and see the cue ball heading for the thirteen. Would you know, using your reason, that the thirteen ball would move a certain way? Couldn’t the thirteen roll backwards? Couldn’t it spontaneously combust? Since what actually happens to the thirteen is a matter of fact, each of these scenarios are logically possible.

One cannot discover the cause in the effect because the cause and the effect are distinct, they are different events. They just happen to occur in conjunction. In other words: there is nothing in the event of the cue ball hitting the thirteen ball that necessitates the thirteen going just that way.

Why, then, do we believe that there is actually something connecting these two events, that one necessarily causes the other? Hume says that is simply the power of custom.

Cause and Effect: Necessary Connection?

More on NecessityWe all agree that every effect is

determined by a cause, and a specific cause.

Effects are not random events; rather every effect is precisely determined by the content of its cause such that no other effect could result.

You decide to bake a cake using the following ingredients: flour, sugar, eggs, milk, baker’s chocolate, and chocolate chips. Will the cake taste like cinnamon? No! The effect (the cake) is precisely determined by the cause (ingredients); the result is tightly connected to what you put in.

Constant ConjunctionIf all our experience of the world were such

that no two events or objects bore any similarity to one another, each was totally and completely new, then we would have no concept of necessity.

We could only say that one event followed another in time, not that one event caused another.

But, there is similarity between objects and between events. Similar events follow one another in such a uniform fashion that they become constantly conjoined in the mind; from the occurrence of one we infer the occurrence of the other.

This is necessity.Everyone actually believes this concept of

necessity holds for not only physical objects but for operations of the will. Controversies and debates have arisen due to misunderstanding one another and semantic disputes.

History as Support for CCWhy study history?To unearth the constant and universal

principles of human nature by examining human beings in various situations.

War, revolution, political intrigue, etc. are all data for acquainting us with the sources of human behavior, from which we can generalize about human nature.

Elements examined by ancient scientists yield the same data as they do if studied today and medieval experiments concerning these elements would yield the same results if repeated today. So too with human beings: historical data can tell us anything we want to know about contemporary human beings.

The fact that analysis of human action holds any bearing upon prediction of contemporary human action lends support to the hypothesis that human action is necessary (in Hume’s sense).

Traveling Tales

Consider the following: Suppose a traveler returns from her excursion to a newly-discovered land. She proceeds to tell stories of the people she encountered. According to her, these people lack vices such as greed, selfishness, ambition, etc.

You would probably be skeptical of her tales. In fact, you’d probably believe that she was lying. Hume claims that such a person might as well be telling stories of centaurs or dragons.

Why? We are aware of the general principles of human nature due to our experience. We have observed the constant conjunction of motive/intention/expression and a certain action. Human beings behave in certain ways, necessarily.

Necessary Conditions For TheoryWith knowledge of general principles of

human nature, we can guide our future conduct. We confidently build theories concerning human beings.

Actions can be inferred from knowledge of motives, and motives can be inferred from knowledge of actions. We don’t expect things like selflessness, by a group or an individual, at any level of society.

These inferences and theories are empirical facts. So, think about what is necessary for these facts to come about. They would not be possible without the uniformity and general patterns of human action. Otherwise, all the experience in the world would serve no purpose in regards to forming generalizations about human beings.

Before You Get The Wrong Idea…Hume is NOT saying that all human

beings behave exactly the same.Complete and total uniformity is

never observed anywhere in nature, so it is quite obvious that human action will exhibit some variety.

There exist a variety of generalizations concerning behavior’s relationship to motive, but this variety (perhaps even the concept of variety as such) presupposes an underlying uniformity.

Causes and effects are not all conjoined uniformly.

Unexpected Effects, Uncertain CausesThe common, vulgar, uneducated

view supposes that an unexpected outcome reveals that there are some “uncertain” causes, that necessity is undermined.

Scientists realize that there are various, often competing causes occurring at the micro level that produce necessary effects.

For instance, when a medical treatment is not working, the doctor doesn’t doubt the (necessary) cause/effect relationship of medicine or the certainty of the general principles of medical science. She attributes the unforeseen effect to hidden or previously unknown causes.

Consistent With Constant ConjunctionIf we are to be consistent, the same holds

true for human action. Seeming irregularities can be explained with a bit of circumstantial knowledge.

A man who receives his paper quite cheerfully every morning is irritated this morning. Does that call into question the cause/effect relationship between him and the paper? No. He has a toothache.

Also, inconstancy is the constant character of human nature in general, especially for those who do no operate according to a fixed rule of conduct.

The relation that holds between character and conduct and between motive and voluntary action is just the cause and effect relation. It is necessary, regular and uniform.

Similar Necessities

Consider the following argument:(1) A prisoner is physically caged in with stone walls and iron bars(2) He has no money or influence(3) The jailer is stubbornly unwilling to permit his escapeTherefore: The prisoner will not escape.What is interesting about this argument? The connection of (1) to the

conclusion and (2) and/or (3) to the conclusion is the same kind of connection in our mind. We don’t feel any different about the certainty of the necessary connection of (2)/(3) to the conclusion because it involves the necessity of of human actions.

The constant conjunction of motive and action have the same effect on us as the constant conjunction of physical objects or events.

MisunderstandingWhy do we behave and conduct ourselves as

if human action is governed by necessity (Hume’s kind) but proclaim the contrary?

Hume believes that it is because we misunderstand the notion of necessity.

Experience never gives us more than the constant conjunction of objects or events, and based on this we fall into the habit of inferring from the occurrence of one event to the occurrence of the other.

However, many think that they perceive something beyond this, a necessary connection because one event and another. Of course, when you think about any experience of cause/effect, then you realize that the metaphysical notion of necessary connection is super-added to experience.

But, once we grasp that necessity = constant conjunction + habitual inferences, then it seems that voluntary action is also necessary action.

Humean Humility Makes It EasierBeginning an inquiry into the nature of

the will with an examination of operations of the mind leads to error.

One ought to begin with the operations of matter and the causation relations therein and determine the nature of their necessity.

Beginning the inquiry with a defective notion of necessity is to make the whole issue impossible to resolve.

We must be able to admit the limitations of our understanding by allowing that the only kind of necessity we are given by experience is that of constant conjunction.

Metaphysical LibertyNot only do we all actually agree about

necessity, but we all agree about metaphysical liberty (freedom) as well.

What does freedom mean when applied to voluntary action? Surely not that actions have so little connection to motives, inclination and character that the former do not follow the latter with a certain degree of uniformity! There would be no way at all of predicting human action.

So, by freedom of voluntary action, we must mean the ability to act according to the determination of the will( free action = to do what you want to do).

Any definition, if it is a good one, will operate within the following constraints (1) it must be consistent with matters of fact, (2) it must be consistent with itself. Hume claims his definition of metaphysical liberty fits within those constraints.

Unnecessary Cause? No ChanceNothing exists without a cause of its

existence, and there is no such thing as a cause that is not necessary.

Is it even possible to define the concept of causality without reference to necessity (Hume’s or the common version)?

Metaphysical liberty is freedom of constraint, not freedom from necessity. If it is freedom from necessity, then metaphysical liberty is equivalent to chance.

Chance is not a real power or existence in the universe, for, as we said, every existence or event has a (necessary) cause.

Constant Conjunction and Responsibility

No reasoning is more common or more blameworthy than that of trying to refute a philosophical theory by claiming it is dangerous to morality or religion.

Dangerous does not equal false.Such a line of argument does not contribute to the discovery of truth; it

simply makes the arguer “personally odious.”Hume claims, though, that his own view of liberty and necessity not only is

not dangerous to moral responsibility but , in fact, is essential to it. So, it is good to know that moral responsibility would not be threatened if

someone discovered a necessary connection between physical cause and effect that is beyond constant conjunction + habitual inferences. Such a discovery would have bearing on empirical science but on the operations of the mind, which we all agree are rooted in constant conjunction causality.

Moral Law Depends on Necessity

All law is founded on the concepts of reward and punishment.

This truism is based on the fact that rewards and punishments have a regular, uniform influence on the human mind. Such influence is the cause of people preferring to do good and avoiding evil.

Argument From PunishmentWe blame and punish a person, their character, and

not actions that persons commit.Let us adopt the “freedom from necessity” definition

of liberty. Then, actions do not come from some cause in the character of a person, so the persons are not praise/blameworthy, they are not responsible. Actions don’t arise from anything inherent in the person.

So, if voluntary action is not governed by necessity, a murderer and a newborn child are equivalent in purity of character, since there is no connection between character and action.

Consider: people are not morally blamed from accidental actions or ignorant actions even if they result in bad consequences. Why is this? Because in such instances, there isn’t a connection between their action and their character.

Consider again: repentance wipes away moral guilt for crimes. Why is this? The person undergoes a fundamental change in character.

So, to safeguard the notion of moral responsibility, it seems like voluntary actions are governed by necessity.