Desires Cannot Fulfill Or Thwart Other Desires

In his post Living Without A Moral Code, part 3, Luke Muehlhauser writes,

Now, it seems straightforward that my carnivorous desires are immoral. Surely my desire to eat meat tends to thwart more and stronger desires than it fulfills. It certainly thwarts the desires of the animals I eat, both by way of their death and by way of their horrifying lives packed into factory farms.

That is incorrect. Desires cannot fulfill or thwart other desires.

Luke and Alonzo define morally good desires as “desires that tend to fulfill other desires,” and argue that we should use praise to promote them. Conversely, they define morally evil desires as “desires that tend to thwart other desires,” and argue that we should use condemnation to promote aversion to them. Yet, if desires are mere propositional attitudes as Alonzo also claims, then it is logically impossible for a desire to either thwart or fulfill other desires. If I was sitting next to you on the train, and you had the desire to breathe clean air, my desire to smoke could not possibly thwart your desire to breathe clean air. Only acts and the states of affairs created by them retain the ability to thwart or fulfill other desires. Simply put, desires cannot fulfill or thwart other desires unless acted upon. Only my lighting up a cigarette can thwart your desire to breathe clean air.

So why are desires the objects of evaluation in desirism? Is it simply a branding decision to make desirism more attractive on the shelf of moral theories? Or, is there a reason for making desires the objects of evaluation as opposed to acts?

Granted, intentional acts seem to flow from desires in every conceivable instance, so it makes sense to aim praise and condemnation at desires. If you can remove evil desire X from the population, then you effectively preclude all instances of evil act X therein. I see nothing controversial with that line of reasoning. Rather, I question the supremacy of desire fulfillment in moral evaluations. Don’t get me wrong; I think “desires fulfilled and thwarted” are certainly a component of morality, but they simply cannot be the guiding criteria because even evil desires can “tend to fulfill other desires” if the “other desires” are predominantly evil to begin with.

What about the “no harm, no foul” policy?

Take the desire to cheat on one’s spouse as an example. Alonzo might argue that “people generally” have many and strong reasons to promote an aversion to infidelity, but there are at least two angles I think we need to consider. For one, I’m not sure it’s true that “people generally” have many and strong reasons to promote such an aversion. At first glance, it seems to me that single people have no such reason. I suppose one could invoke the phenomenon of collateral damage and claim that even single people have such reason, because infidelity can lead to expensive trials that burden the legal system and cause serious psychological damage, especially when they are children involved. Even still, it seems a bit of a stretch to claim that single people or those committed to non-monogamous relationships have any reason to promote an aversion to infidelity.

What does it mean to say that we should “promote an aversion to infidelity,” anyways? Should we spread anti-infidelity propaganda? This is in fact what happens in other instances. For example, you might see a poster at a bus stop which condemns bigotry against homosexuals and other minorities. On further reflection, I don’t recall ever once seeing a poster that condemns infidelity. Yet, our culture is literally saturated with posters and propaganda that condemn bigotry against minorities. What, if anything, can we infer from this?

Further, could a “bad desire” actually be beneficial to the agent? Recall that desires cannot thwart or fulfill other desires unless acted upon. What of various arguments for the psychological benefits of sexual fantasy? Here we at least potentially have a class of desires which would tend to thwart other desires if acted upon, but would actually tend to fulfill other desires when not acted on. In the case of married individuals, sexual fantasies constitute genuine desires for infidelity – desires I’m guessing Alonzo Fyfe would say “people generally” have reason to condemn – yet, on what grounds?

Where is the justification for the across-the-board policy of condemning desires that tend to thwart other desires? Since desires are brain states, isn’t this simply the desirist version of the thoughtcrime objection atheists often level towards Christianity? To that end, Luke remarks,

Christianity [claims] that we are ruled by an all-powerful dictator who convicts us of thoughtcrime and will torture us if we do not bow before him – like an everlasting Jafar with unlimited wishes.

What, exactly, is the difference between Jesus condemning adultery in the heart and the desirist condemning adultery in the brain?