The “many agents” view of the mind
One of the commonest images of the mind involves two “internal” agents struggling for supremacy: “reason” versus “the passions”. It is held that a wise person manages to subdue his unruly passions with his still more powerful reason. Or at least he can keep his passions in check to live a balanced sort of life.
The supposed antagonists in this struggle are reason, singular, and the passions, plural. Why this numerical imbalance? – The vague idea seems to be that reason is self-consistent, and as such it cannot come into conflict with itself, so there’s only one of it. But the passions are not constrained like that – they pull in all sorts of different directions, so there are many of them, or at least more than one of them. (There may be an element of truth in that: our desires can come into pragmatic tension with one another in a way that our beliefs cannot.)
Plato fine-tuned this simple reason-versus-the-passions model of the mind. In his dialogue Phaedrus, Plato likened the soul to a chariot, pulled by the horses of appetite and indignation, with reason in the driver’s seat. This tripartite model of the mind has been influential. For example, Freud’s model of the mind is at least reminiscent of Plato’s, with the conscious “ego” playing the role of reason, and the unconscious “id” and “superego” playing the lustful horse of appetite and the moralistic horse of righteous indignation respectively.
Although there may be some useful suggestions in such models, they are all misleading in that they treat components of the mind as if they were agents in their own right. But any real mind is at most a single agent.
Why do so many models of the mind commit “the homunculus fallacy” of positing internal agents with minds of their own? I think part of the explanation is that we habitually suppose that the mind is “cut off” from the outside world, with the result that motivation begins to look like a bit of a mystery. If the mind is in effect insulated from the outside world, then our primary ends can’t be to realise this or that external state of affairs, but instead to achieve more proximate internal goals – i.e. to enjoy experiences such as pleasure. Since so much of what we choose to do does not obviously bring pleasure, the question arises: what sort of experiences can we be “really aiming for” then? If what we’re “really after” are consciously-experienced feelings of one sort or another, we have to divide up our motivating urges into those that reward us with this or that type of conscious experience. Among these, we find “baser” urges to get the pleasure of sex, or to avoid the pain of hunger. Then there are “higher” urges to get the satisfaction of being factually correct or morally right. Highest of all are those motivated by the purity of reason alone, if that even makes sense. The mind begins to look as if it is populated by “thrifty housekeepers” who deal with the “home economics” of deferring this type of pleasure for that, who insist on “tightening our belts” by having us make do with a bit of pain for now, knowing that it will be offset by greater pleasure at later date. Then there is the saintly housekeeper whose sole purpose is to use reason and do right.
It should be obvious that this is a ridiculous image of the mind. It’s completely disconnected from evolutionary theory, and it ignores the obvious fact that the simplest animal minds evidently seek external goals without having to engage a complicated internal apparatus of thrifty or saintly housekeepers doing home economics of conscious pains and pleasures.
Hume on belief and desire
Let us return to the fact that any mind is part of a single agent. David Hume saw that real acts are the products of both beliefs and desires – in other words, mental states of thinking that such-and-such a state of affairs is in fact the case, and of wanting such-and-such a state of affairs to become the case. (Hume’s famous distinction between “is” and “ought” reflects this difference, since to Hume morality is a matter of “sentiment”, of wanting what others want as a result of our fellow feelings for them.) Furthermore, according to Hume “reason is the slave of the passions” – in other words, the purpose of our beliefs is to help realise our desires.
Although Hume used the metaphor of a “slave” here, and real slaves are of course agents of sorts, Hume’s understanding of action goes against models that posit further agents within the actual agent. Hume wasn’t simply reversing the roles of Plato’s horses and charioteer: for Hume, belief and desire are the two essential component mental states behind the act of any single agent. If an agent desires X, and believes that action A will achieve X, he performs action A. The point of seeing reason as an out-and-out “slave” of the passions is not to add an extra internal agent, but remove the explanatory need for one, by stressing how integral reason is to any sort of agency.
I often use the rudimentary example of a cruise missile to illustrate this idea. A cruise missile has a goal (to hit its target) and an on-board map which it uses to steer its way towards its goal. Having such a goal is its rudimentary analogue of desire, and the map marking the missile’s current position is its rudimentary analogue of belief. We can think of its “passions” as everything involved in its being directed towards its target; and we can think of its “reason” as everything involved in figuring out its actual position. Then both are essential components in its “acting” to achieve its goal. And “act” it does, in a rudimentary sort of way, because it is a rudimentary sort of agent.
Hume’s theory of action was a breakthrough. Its naturalism saw “the passions” as goal-directed states rather than as internal agents liable to lead us astray like internal will-o’-the-wisps. So it removed a sort of middleman. Without Hume, one might wonder why an agent would go for this or that external goal. The “explanation” would involve drawing a link between acting to achieve a goal and “having the motivation” to act – which involves an internal “weighing” of prospects of experiential rewards. With Hume, the internal reward looks unnecessary.
In keeping with current usage, I shall call goal-directed mental states “desires” and fact-representing mental states “beliefs”. In these terms, Hume showed that desires cannot be “mistaken”. They might lead to a miserable life, or a premature death, or worse: “’Tis not contrary to reason to prefer the destruction of the whole world to the scratching of my finger.” Because desires do not even purport to represent the world as it actually is, they cannot conceivably be corrected for misrepresenting it. Nowadays we might call it a “category mistake” to assume that desires can be mistaken.
Can we have “mistaken” desires?
I think the widespread sense that we can be mistaken about what we want is an example of “the bewitchment of our intelligence by means of language” – one that arises through an ambiguity. Suppose I report my own mental state by saying “I want some wintergreen-flavoured chewing gum”. But after actually tasting it, I seem to correct myself by reporting that “I didn’t really want that after all”. It seems to me that I have either changed my mind, or else must have originally misreported the content of my desire. In either case, the desire itself wasn’t mistaken. If I changed my mind, I ended up with a different desire, but that’s not the same as starting off with a mistaken desire. On the other hand, if I misreported the content of my desire, I had a mistaken belief. How might I misreport the content of my desire? – One obvious way is by being over-precise. Perhaps all I wanted was a “refreshing, mouth-cleansing” flavour, and mistakenly thought wintergreen would deliver it. My mistake was believing that wintergreen would deliver what I wanted, rather than having a mistaken want. I “wanted the wrong thing”, but what was wrong was my belief, not the want itself.
Yet the idea that desires can be mistaken seems to have a life of its own. It permeates the “positive” concept of liberty (as Isaiah Berlin called it) that has been mainstream in Continental European philosophy. According to this conception, being free isn’t simply a matter of being able to do what you want, whatever that may happen to be. It also involves wanting the right things, in other words having supposedly non-mistaken desires. Rousseau, Kant, Hegel and Marx all treat reason as if it can determine goals, and as if some goals are “unreasonable”.
There is a sinister side to the assumption that some of our desires can be mistaken, which involves overruling “mistaken” desires, or treating them as “not really desires at all”. The former entails paternalism – forcing people to do things for “their own good”. The latter involves dismissing desires as the illegitimate products of “false consciousness”, “brainwashing”, or something similar.
This is all well-trodden ground. As old-fashioned liberals from Burke to Berlin have repeatedly argued, that way lies the gallows, the gas chamber and the Gulag. Rather than going over such familiar ground again, I’ll look at some positive results of Hume’s understanding of belief and desire.
By treating belief and desire as necessary but separate components of the causation of action, it’s much easier to see the difference between them, and to logically “isolate” each type of state from the other. We can think about how beliefs mesh with other beliefs of the same agent, and how desires mesh with other desires of the same agent.
“Systems” of belief and desire
Taken together, an agent’s beliefs form a system. WVO Quine argued that we should think about that system as a “web”. Beliefs hang together through relations of implication. If one of them must be excised from the system, because it threatens contradiction in the light of a new observation say, at least some of the others that together imply it must be excised as well. There are no “foundations”, although some are anchored more directly to the world through observation than others. By always minimizing disruption to the system as a whole, new observations can be accommodated – and as they are so accomodated, the system evolves over the course of time.
An agent’s desires also form a system, although it is less systematic than a richly-interconnected “web”, because individual desires aren’t subject to the relations of implication that exist between beliefs. (Perhaps the strongest constraint is that no agent can both desire X and desire not-X at the same time.) Like an agent’s system of beliefs, his system of desires also evolves over the course of time. As far as I know, JS Mill was the first to suggest a metaphor (in The Subjection of Women) that it grows like the branches of a tree. Infants start out with a few, coarse-grained desires for large-featured, roughly-circumscribed objects such as food, contact with parents, and warmth. As time passes, and as their powers of discrimination are more finely tuned, these desires increase in number and become focused with greater sharpness on particular types of food, particular kinds of interaction with particular people, warm water rather than hot air, and so on.
The tree metaphor is intended to capture a few salient psychological facts. First, desires don’t just spring up “out of the blue” as a result of mere exposure to some sort of stimulus. They develop from – i.e. grow out of – earlier desires for something less specific, objects of desire that were represented in the agent’s notional world in a coarser, less well-defined way. So the “growth of the tree” of an agent’s desires is the result of increasing fineness of grain and sharpening focus. The newer shoots at the tips of growing branches of a tree are independent of one another – at least to the extent that they cannot occupy the same space – but they are not independent of the older branches they grew out of. Second, the older branches don’t die away when they spawn their newer, more numerous and more finely-focused offshoots: an adult’s coarse-grained desires for food or warmth are just as real as an infant’s desires for the same things. But being longer-established and better-developed, there’s a lot more to them. This is relevant if we consider the satisfaction or thwarting of desires. The longer-established an agent’s desire is, the more it tends to qualify as an “important life interest” and the less fleeting its goal. For example, it is disappointing to get turned down for a job after an interview, or to suffer a miscarriage. But to lose a career you have spent decades carving out, or to have an adult son or daughter die are catastrophes. The passage of time turns green shoots into hoary old branches with multiple offshoots of their own. My concern for my sons isn’t just for their lives, but also for their health, careers, love lives, reputations, friendships, ambitions, and much else besides.
It seems to me that these metaphors of a “web” of belief and a “tree” of desire are well worth exploring. They help to illuminate crucial differences between belief and desire. Apart from the main functional difference noted by Hume, the systematic links between beliefs are “horizontal” while links between desires are “vertical”. That is to say, we rationally adopt new beliefs and abandon old beliefs by checking how well the current system hangs together logically. How new beliefs arise is mostly irrelevant – the context of discovery is independent of the context of justification. But we adopt new desires and abandon old desires not as a matter of rational choice, but as a matter of historical development. A belief system does not have foundations, but a desire system does, in a manner of speaking.
To see how this view differs from that of someone who has a “positive” concept of freedom and who thinks we are liable to fall victim to “mistaken desires”, consider advertising.
It is quite common to think about advertising as if it can implant a wholly new desire – a “mistaken” desire – in the mind of someone exposed to it. This thought comes from being unclear on the difference between belief and desire, and taking belief as the generic model of a mental state. It’s true that exposure to new facts often gives rise to new beliefs about those facts. But desires are different from beliefs. A desire for something can only be implanted in the “receptive, fertile soil” of a mind that wants something roughly like it already. You might not have thought of buying an iPad, say, till you see an ad for one. But an ad for an iPad won’t sway you unless you already wanted some sort of useful computer-like gadget or reading device. I would argue that all advertising can ever implant are desires of greater specificity than before. Since greater specificity is an inevitable result of the passage of time and the sharpening of the focus of desires that already guide behaviour, it is largely irrelevant that it delivers the goods for Apple rather than Amazon on this or that particular occasion.
Animals use “advertising” when they brandish ornaments of sexual selection to entice sexual partners. The classic example is the peacock’s tail. The purpose of the tail and the advertising is to attract peahens. It also happens to attract the eye of human aesthetes, and the unwanted attention of predators. In all three cases, desires that are already in place are focused more precisely on a particular peacock. The peahen must be already interested in sex with peacocks, the aesthete must be already in search of objects of beauty, and the predator must be already hungry. This animal advertising serves a “purpose” in much the same way as human advertising is deliberately aimed at attracting the attention of potential buyers. But its effects depend on whether or not it is noticed, and that is a matter of the receptivity of who or what is noticing. Whether it is purposeful, deliberate, or wholly unintended, all that happens to who or what is noticing is their range of options is narrowed rather than enlarged.
Political distaste for the “consumer society” and the supposed victims of its advertising campaigns fuels the idea that there are “hidden persuaders” at work, “brainwashing” us into wanting things we wouldn’t otherwise want at all, or shouldn’t want for moral reasons.
I would welcome an end to that way of thinking. I think it harms more people than it imagines fall victim to “false consciousness” or the “consumer society”. For example, those attitudes have done untold harm to homosexuals, who were traditionally thought to corrupt non-homosexuals. But if we were clearer about the differences between belief and desire, we would see that “radical conversion” of that sort is impossible.