It seems to me the way people tend to think of desires and decision-making in every day life these days is something like this:
Desires come upon you, from who-knows-where, biology or whatever. Fulfilling desires often comes with some costs -- either you have to pay money, or you have to do something you don't want to do, or you can be punished if the desire is for something bad. If you're rational, and even semi-normal, you take this information, about your desires and the costs of fulfilling them, and you use it to form a kind of system of preferences -- you want this more than that but less than the other and so on. Then you use this to decide what to do.
This is fine as far as it goes. And if you're trying to decide whether to spend 90 dollars on cool new Timberland high-heeled allusively styled boots, as I recently was, I suppose it's not a bad method. But isn't it weird that no where in that story is there a step where you consider how your action is going to affect the desires you later have?
The problem with this method is that there's no room for desire management.
Managing your desires, obviously, means making decisions based partly on how the action in question will affect your later desires. Here's an example, drawn, naturally enough, from a Victorian novel. The Victorians, it seems to me, were great ones for desire management: society had these grooves that you could hardly fail to fall into; keeping out of them required great effort; once you were in a particular groove you'd be much more likely to have desires that were apt for your health and happiness, and also appropriate for your social position.
In Trollope's classic and wonderful novel, Can You Forgive Her?, the heroine, Alice, starts out engaged to be married to a nice but maybe slightly boring guy. In the story, she loves this guy, but she's not really so keen on the life she expects to lead after marriage: she's a feisty sort of person, interested in politics and city life, and her husband-to-be is a quiet living man, who enjoys spending time in his country home and reading books.
Right at the beginning of the story, she gets invited to join her old friend, and her friend's brother, on a trip. The friend's brother, it turns out, is an old flame, and is kind of a wild person. Everyone around Alice immediately sees the difficulty. They start nagging at her day and night: do not go on this trip! Alice, of course, is exasperated and points out that if she loves her fiance, which she does, what harm can it do? To this her nearest and dearest simply point out the impropriety of what is being proposed. Alice forcefully argues that she cares nothing for merely doing as she's told, and certainly is not planning obedience to anyone, so how can this sway her?
Of course Alice does go on the trip, and of course she does change her mind about her fiance, and of course it is clear to the reader that she is wrong to do so. What happens is that being with her friend and her former flame causes her to see the world differently, to value her own independence and fiery personality more, and to value her fiance, and her love for him, less. Those grooves of Victorian society, had she followed them, would have prevented this sad state of affairs, that is, they would have prevented her from changing her preferences from those that were ultimately best for her to those which were not.
Now, it's not that I want to return to the Victorian grooves of society -- obviously those particular grooves won't work for us. But really, we've got nothing like this at all. The only time I hear anyone worry about how context will affect their desires and choices is when someone is recovering from addiction: addiction is the only model we have for why we'd say things like "Don't go to that party, don't go to the bakery, don't go on that trip with your former flame, because if you do you'll make choices you'll regret later."
But really, you don't have to be any sort of addict to have your preferences and desires be shaped by your surroundings. You just have to be human.
So I feel desire management is kind of a lost art. But wouldn't a little help in this domain be nice? Instead of, Oh, you want to watch TV and eat junk food but you have to weigh that against the cost of being dumb and out of shape, we'd have something like, Here, do these things, and rather than wanting to waste your time watching Friends reruns and eating Cheetos, you'll prefer to spend your time playing soccer or learning another language.
The desire-satisfaction model we've got, it just has no room for these really crucial forms of reflection. Desires don't always come from nowhere. Sometimes they arise as the predictable outcomes of your own decisions.