I’m currently reading Kim Sterelny’s Thought in a Hostile World (Blackwell/Wiley 2003). Part of why I’m reading it is for the purposes of this common currency project. (The book as a whole is profoundly interesting and worth reading.)
Thought in a Hostile World is concerned with two related projects concerning the cognitive evolution of humans. One is about the ‘wiring and connection facts’ from the perspective of a theory of human agency, and evolutionary history. The other concerns the relationship between the wiring and connection facts, and a second set of ‘interpretive’ facts. These interpretive facts (about humans) include belief-desire folk psychology, but also sciences such as economics and anthropology which work with what Sterelny calls “refined versions of our folk self-conception”.
With respect to belief Sterelny argues on the one hand that many examples of successful control systems can get by with less than beliefs, and on the other than some specific types of cognitive demand would explain the evolution of belief-like states, because they require ‘de-coupled’ representations. These representations encode information that cannot be reliably extracted from single cues, that are potentially relevant to many actions, and which may be relevant at times other than when the information is perceptually salient.
After three chapters mostly focused on belief, and belief-like states, Sterelny devotes on (Chapter 5, pages 78-96) to “The Descent of Preference”. I don’t yet have a settled view about what Sterelny has to say here. But it is definitely relevant and important for anyone thinking common currencies for action selection:
- Although making no direct reference to common currencies, and surprisingly little to the economic aspects of choice, Sterelny is concerned with the natural history of preference, and with the question how an agent with a preference structure of some kind (he does occasionally use the expression ‘utility function’) might behave differently from one without.
- He argues that preferences are like belief-like states (‘decoupled representations’) in being found only in some animals, and in response to specific cognitive challenges that cannot be solved by simpler means. Sterelny is (it seems) agnostic about whether rats exhibit the required sophistication, but thinks that primates definitely do.
- So, depending on what exactly Sterelny means by preferences, his view is some kind of partial eliminativism about preferences (some animals may seem to have them, but if you use the right criteria you’ll see that they don’t need them). It would seem to be a consequence of this position that common (cognitive) currencies are relatively rare and unusual.
Part of the reason I don’t yet have a settled view about Sterelny’s chapter on “The Descent of Preference” is that I’m currently downright puzzled by some of the decisions he seems to have taken in the chapter. Among them:
- The companion to belief in intentional psychology is desire. In previous chapters he’s been careful to explain how belief-like states and decoupled representations are pretty close to beliefs, without (very reasonably) calling for them to be identified. Yet in this chapter he mostly talks about preference as opposed to desire. It’s consequently less clear what explanatory target he’s aiming at.
- This is made worse by some of the things he says about preferences. So at one point he describes the task of the chapter as giving an account of “motivation based on representations of the external world.” Beliefs are paradigmatically representational states. And desires are supposed to interact with beliefs. But why make desire itself (or preference) primarily representational? The main theories of desire on the market are mostly non-representational. They have it that desire is a disposition to action, or has something to do with pleasure, attention, learning. (There are fairly representational theories of desire too, but they’re hardly the most congenial to Sterelny’s natural history of cognition.)
- Sterelny organizes some of his discussion by reference to what calls ‘the forager’s dilemma’ (which he does not clearly define in the chapter). But he says surprisingly little about what I above called the ‘economic aspects of choice’. I have in mind here the problem Robbins (1935) formulated as that of allocating “scarce means which have alternative uses”. Any agent with a relatively rich behavioral repertoire faces a trade-off problem in allocating resources between available actions. Many actions are mutually exclusive, either directly or in drawing from a common energy budget. The costs of far-from optimal allocation might be very high. I haven’t yet figured out why Sterelny says relatively little about this kind of issue.
Still, it’s a fine book and well worth reading. I’ll develop some more systematic reflections on it in due course, and post them here where they can be safe from prying eyes. (I'll also comment on some of the earlier papers in which Sterelny developed some of the ideas that appear in Thought in a Hostile World.)
Robbins, L. (1935) An Essay on the Nature and Significance of Economic Science. London: MacMillan and Co.
Sterelny, K. (2003) Thought in a Hostile World. Oxford: Blackwell.