Friday, September 15, 2006

Desire Utilitarianism vs. Act Utilitarianism

My new plan is to devote the weekend posts to moral theory, and talk about moral application on weekdays.

This weekend’s topics are:

Today: Desire utilitarianism vs. act utilitarianism

Tomorrow: “Choosing” a moral theory

Desire Utilitarianism’ and ‘Act Utilitarianism’?

This blog is based on a theory called “desire utilitarianism.”

Many people who hear this term immediately assume that I base it on a theory that says, “Do that act that provides the greatest desire fulfillment for the greatest number.” Some will provide objections to such a theory, explaining how difficult it is to determine the act that brings the greatest desire fulfillment for the greatest number. Some will point out how it is sometimes possible that slavery or genocide will bring about the greatest desire fulfillment for the greatest number. Some will challenge me to prove to them that they should choose to be a desire-utilitarian, and assert that I cannot come up with an objective answer to that question.

All of these objections fail, because desire utilitarianism does not say, “do that act that brings about the greatest desire fulfillment for the greatest number.”

The theory that would make this claim is an act utilitarian theory. It is a theory that says, “Do that act that provides the greatest utility.” It then defines “utility” in terms of desire fulfillment. However, the primary object of moral evaluation is still the act.

Desire utilitarianism says that the primary object of moral evaluation is the desire. To make moral evaluations, the first thing we are going to do is evaluate desires – classify desires as ‘good’ and ‘bad’. Once we have this information, then we are going to classify acts as acts that correspond to ‘good’ desires and ‘bad’ desires. Desire utilitarianism does not say, “Do that act that provides the greatest desire fulfillment for the greatest number.” It says, “Do that act that corresponds to good desires.”

The classic distinction in utilitarian moral theory is the distinction between act-utilitarian theories and rule-utilitarian theories. Act-utilitarian theories say, “Do that act that produces the most utility.” Rule-utilitarian theories say, “Do that act that corresponds to good rules, where good rules tend to produce the most utility.”

Desire-utilitarianism is a rule-utilitarian theory. What desire-utilitarianism adds to rule-utilitarianism is the claim that the ‘rules’ are written into the brain in form of desires. These rule-utilitarian rules are not just any old rules that somebody happens to imagine. These rule-utilitarian rules are desires. As such, these rules have all of the properties and limitations that of desires, and this affects how rule-utilitarianism works.

The Fatal Flaw of Action-Based Theories

The basic problem with theories that state that the evaluation of actions is primary is that they skip over the very important fact that they ignore the causes of intentional actions – beliefs and desires.

A person comes to the road. He has a choice to turn left or right. What determines his choice is his beliefs and desires. He will take the turn that he thinks will lead to the greater fulfillment of his desires, given his beliefs. If anybody wants this person to turn in the other direction – this requires changing either his beliefs or his desires. Arguing for a turn in a different direction while holding the agent’s beliefs and desires constant is nonsense. It cannot happen.

So, any ‘ought’ recommendation applied to an action must imply a change in the agent’s beliefs and desires. Furthermore, that change must be a change that will cause the agent to perform the recommended action.

If I had room, I would give an argument for removing beliefs from consideration and focusing entirely on desires. In the space I have, I am merely going to assert this. Beliefs map to truth. A person should have a belief that P only if P is true; if P is false, than an agent should not believe that P. Since belief already maps to truth, this leaves desire to map to value.

That is to say, to change a person’s choice, we must change their desires.

However, a change in desire is not only going to affect this action, but all other actions where that desire is relevant. We would be foolish not to consider all of the effects of any change in desires. When we begin by evaluating desires, we move from act-utilitarian theory to desire-utilitarian theory. Desire utilitarian theory fully considers the causes of human action.

Note: Desire utilitarianism, as a moral theory, also does not require free will. In fact, it actually requires determinism. Desires are the primary object of moral evaluation because intentional actions are caused by desires.

Revisiting the Objections

Now, let’s look at some of those objections to act-utilitarian theories:

(1) It is difficult to determine the act that brings the greatest fulfillment to the greatest number.

This is true. However, it is far less difficult to determine the effects of particular desires on the fulfillment of other desires. An act of rape might produce good consequences. The victim might be motivated to study the psychology of rape and come up with a way of treating sex offenders so as to drastically reduce the number of rapes. These would be good consequences. The act-utilitarian theory would then have to say that this particular rape was a “right action.”

Desire-utilitarianism asks whether the desire to rape will tend to produce good consequences. It might be the case that, under some highly unusual circumstances, a particular rape may do more good than harm. However, desire-utilitarianism does not care about this. It cares about the overall tendency of the desire to rape. There, it is quite reasonable to conclude that the tendency of the desire to rape is to thwart other desires. If nobody had a desire to rape, there would be fewer desires being thwarted. Consequently, we, as a society, have reason to pursue a state where the desire to rape does not exist.

It is hard to predict the consequences of any given lie, but it is not so difficult to predict the consequences of a widespread aversion to lying. It is hard to predict the consequences of any particular theft, but not so hard to predict the consequences of an aversion to taking property that belongs to another.

It is sometimes possible that slavery or genocide will bring about the greatest desire fulfillment for the greatest number.

Actually, I see the claim that slavery or genocide can produce maximum desire fulfillment to be like the claim that pigs can fly. The fact that people can imagine something does not prove that it can happen. The problem with slavery and genocide is that it is not possible – not in any real-world sense – that they can bring about maximum desire fulfillment.

Take slavery, for example. We are asked to imagine a case in which slavery brings about maximum desire fulfillment – the suffering of the slave is less than the greater desire fulfillment of the master. Now, let’s add one small change to the system. The master, who gains, transfers something of value to the slave to compensate for the loss. Because the master gains so much, the master can give much and still end up with a net benefit. Because the slave looses so little, a small gain will be enough to give the slave reason to do the act voluntarily. This one small change in the rule will help to ensure that it is the case that the master always gains more than the slave loses. However, this one little change turns the ‘slave’ into a free and voluntary employee, and slavery no longer exists.

“But, what if we made those changes, and it turned out that slavery produced the most utility.”

Well, then, we would have to rethink the laws of morality – in just the same way that if pigs could fly we would have to rethink the laws of physics. However, we do not have to rethink the laws of morality or the laws of physics in the real world where pigs do not fly and where the absence of an aversion to harming others will create more instances of people doing harm to others.

(3)Prove to me why I should choose desire-utilitarianism over any othe rmoal theory.

This is the subject of tomorrow’s posting.

2 comments:

Dar said...

Would you agree or disagree with the ten commandments as being very basic desire-utilitarianist? (minus the first one)

Db0 said...

Heh, as weird as this is, I have ended up defending DU in the Atheist Nexus :D