Monday, May 6, 2013

Cui bono? Selfish goals need to pay their way


The text below is the un-edited preprint of a commentary I've just submitted to BBS (Behavioral and Brain Sciences). The commentary is about a target article by Julie Y. Huang and John A. Bargh called "The Selfish Goal: Autonomously Operating Motivational Structures as the Proximate Cause of Human Judgment and Behavior".

I have no idea when the commentary might see print. It's a standard joke to say that 'BBS' stands for 'Badly Behind Schedule', and my commentary on Andy Clark's forthcoming target article (see 'My Own Efforts') appeared in another journal before the article it was commenting on. (There was a great flood of people wanting to say something, and some of those who didn't make the first cut had a second change through Frontiers in Theoretical and Philosophical and Psychology.)

As you'll see, I think that Huang and Bargh's proposal faces some serious difficulties. And some of them relate to common currencies.

Abstract

The target article risks not explaining the phenomena, including motivational conflict, that it claims to. The two mains reasons for this are: (1) it is unclear in what sense goals are‘selfish’. (2) We need an account of how selfish goals motivate people. If selfish goals aren’t in the replication business, then what is in it for them? And if they don’t offer people something that they want, how do they ever influence what people do?


Main Text

The proposal in the target article risks not explaining the phenomena, including motivational conflict, that it claims to. The two mains reasons for this are: (1) it is not clear enough in what sense goals might be ‘selfish’, or what incentives they respond to. (2) We need an account of how selfish goals motivate individual people, including how they compete with other incentives to which people respond.

Goals are apparently selfish in a way ‘analogous’ to Dawkins’ (1976) use with reference to genes. Dawkins argued that to understand much of biology it was necessary to take the perspective of the units of heredity. These are ‘selfish’ in the sense that their only interest is in being replicated. Serving this interest sometimes makes demands that oppose the well being of the individual carrying them. Dawkins focuses mostly on units of biological inheritance – genes – but also speculates that there may be analogously selfish cultural replicators or ‘memes’. In the case of memes, as with genes, selection processes favour efficient replicators, irrespective of whether this serves the interest of the ‘host’. In both cases it is clear in what sense the replicators are selfish, and what is ‘in it for them’. The game of life pays replicators with copies of themselves, and the various individuals in which they occur are means to that end. The interests of these replicators are not appreciated by the replicators themselves, but well defined in evolutionary game theory where payoffs are numbers of descendants (Maynard-Smith 1982).

The target article carefully avoids using the term ‘meme’, and makes almost no reference to replication (except in the context of glossing Dawkins’ popularisation of gene-centric selection). This suggests that the sense in which goals are selfish analogously with genes is not the same as Dawkins’ existing meme analogy. But if selfish goals don’t have a primary interest in replication, what are their interests? Goals, we are told, represent ‘end states’, and succeed by being pursued and/or by being completed.

This proposal needs to answer two crucial questions. First, what is ‘in it’ for goals such that pursuit and completion constitutes an incentive? Second, how might selfish goals compete for control of an individual?

It is difficult to discern an answer to the first question, or even clues as to what it might be, in the target article. If selfish goals aren’t replicators and are furthermore in some sense separate from the person they occupy, then they can neither be rewarded with copies of themselves, nor in whatever subjective utility the person responds to. (In any event, in the latter case they would not be selfish at all – they would simply be the person’s preferences.)

The second question is, if anything, even more important. The various (finite) degrees of freedom of any human represent a scarce resource that has alternative uses. That is to say the problem of behaviour allocation is essentially economic (Shizgal, 2012). Some of the processes that implement allocation are peripheral and relatively encapsulated, but most are not. The behaviour allocations of people are undoubtedly sensitive to costs and payoffs, even if it is a matter of controversy what specific economic model humans instantiate. In addition, there is mounting evidence that contemplating or selecting both desirable and aversive options in a wide range of modalities (including money, delayed money, risky money, food, drink, pain, looking at attractive faces, and social reputation) is consistently associated with activity proportional to behaviourally inferred desirability in a single brain region (for a recent review see Levy & Glimcher 2012). Independent of this specific evidence, the motor areas of the brain constitute a final common path for control processes, plausibly requiring any candidate deployment of the agent’s capacities to compete on the same terms as the others.

These considerations apply to selfish goals. The options available to a person (including end-states of goals) are often composed of complex mixtures of components (money, food, sex, status…) and in different modalities. Their availability could be immediate or delayed, and they can be subject to risk. The costs of options also vary in magnitude and type (effort, money, pain, delay…), and may themselves be multi-modal (e.g. including both monetary cost and delay). Making choices in even an approximately efficient way requires trading off these multi-modal options by reference to their net costs and benefits. Arguably, solving that problem is a significant part of what brains are for. Unless selfish goals are to be epiphenomenal, therefore, they need to compete along with the already recognized sources of subjective utility (or reward, or reinforcement), and they need to do so somewhere along the recognised pathways for behavioural control. 

These factors appear to make almost no impact on the argument in the target article, where there is no mention whatsoever of utility, incentive, consumption, pleasure or risk, and merely solitary and passing references to pain, reinforcement, and reward. But selfish goals need to motivate the agents that they occupy, and to do so they need to pay their way in some kind of incentive to which those agents are responsive.

Finally, it is worth pointing out that even non-selfish goals can come into conflict, and that people motivated purely by their own incentives can exhibit inconsistency over time. The most banal of objectives can be mutually exclusive (resting and working, specialising and generalising). All that is needed to explain some conflict, that is, is that not all desires (even those of a self) can be satisfied. In addition, the ways we price in the costs of various ways of being separated from a reward (by delay, risk, effort, etc.) can themselves be a source of inconsistency. This has been most extensively studied in the case of delayed rewards, where there is considerable evidence that humans discount rewards that will be received later (Ainslie 1992, Kable & Glimcher 2007) in a manner that corresponds more closely to a hyperbolic than exponential function. The mere passage of time, that is, can change the ranking of preferences within a single person.

References

Ainslie, G. (1992) Picoeconomics: The strategic interaction of successive motivational states within the person. Cambridge University Press.

Kable , J. W. , and Glimcher , P. W. ( 2007). The neural correlates of subjective value during intertemporal choice . Nature Neuroscience, 10(12): 1625-1633.

Levy, D. J. and Glimcher, P. W. (2012) The root of all value: a neural common currency for choice, Current Opinion in Neurobiology, 22: 1027-1038.

Maynard Smith, J. (1982) Evolution and the Theory of Games. Cambridge University Press.

Shizgal P (2012) Scarce means with alternative uses: Robbins’ definition of economics and its extension to the behavioral and neurobiological study of animal decision making. Frontiers in Neuroscience. 6(20). 


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