The teleological origins of mentalistic action explanations: A developmental hypothesis

In this paper we shall argue that mentalistic action explanations, which form an essential component of a mature theory of mind, are conceptually and developmentally derived from an earlier and purely teleological interpretational system present in infancy. First we summarize our evidence demonstrating teleological action explanations in one-year-olds. Then we shall briefly contrast the structure of teleological vs. causal mentalistic action explanations and outline four logical possibilities concerning the nature of the developmental relationship between them. We shall argue for the view that causal mentalistic action explanations are constructed as useful theoretical extensions of the earlier, purely teleological, nonmentalistic interpretational stance. © Blackwell Publishers Ltd. 1998, 108 Cowley Road, Oxford OX4 1JF, UK and 350 Main Street, Malden, MA 02148, USA. Developmental Science 1:2 pp 255–259 Address for correspondence: Gergely Csibra, Department of Psychology, Birkbeck College, Malet Street, London WC1E 7HX, UK.; e-mail: [email protected]. interpretation. The interpretation works even if it makes reference only to the relevant states of current reality (the presence or absence of obstacle) and future reality (the goal state) as represented by the infant herself. Thus, even without attributing these representational elements to the actor’s mind as causal intentional states (beliefs and desires) present prior to the action, infants could construct a viable teleological action interpretation or prediction. We hypothesize, therefore, that in its initial form the infant’s ‘teleological stance’ generates reality-based explanations for actions that are neither mentalistic nor causal. 2 Teleological versus causal action explanations Teleological explanations differ from causal ones in at least two important respects. First, the explanatory element referred to is in a different temporal relation to the to-be-explained action: teleological interpretations make reference to the outcome that follows the action, while causal explanations point at some necessary condition that is prior to the event. Second, they use different criteria of acceptance: causal explanations single out a prior condition that necessitates the action providing its generative source, while reference to a future state is accepted as a teleological explanation (reason) for a behaviour in case it justifies it, i.e., when, given the constraints of reality, the behaviour can be seen as a rational way to bring about the goal state. As a motto to this article, we cited two paradigmatic answers to the old query about the chicken’s behaviour. Although they sound similar or even interchangeable, the answers represent two different kinds of explanation for the same action. Let us consider them from the point of view of the two differentiating features of causal vs. teleological explanations. In terms of temporal relations, A1 is a classic example of a teleological explanation because the outcome of the action (‘being on the other side’) is cited to account for the event. A1 also counts as teleological in so far as the future state referred to (‘being on the other side’) can, indeed, be seen as justifying the chicken’s road-crossing behaviour. The situation is not so straightforward, however, in the case of the mentalistic explanation A2. In terms of temporal relations, it is like a causal explanation since a prior state of affairs (‘wanting to be on the other side’) is brought up to explain the action. However, when evaluating A2 as an explanation, we do not concern ourselves with whether ‘wanting to be on the other side’ is a necessary precondition that generates road-crossing behaviour, rather, we appeal to the teleological justificatory criterion to see whether ‘wanting to be on the other side’ justifies the action in the circumstances given. This ‘double nature’ of mentalistic explanations is related to the philosophical question whether reasons can be considered as causes in action explanations (Davidson, 1980; Tanney, 1995). Note that causal mentalistic explanations of actions that make reference to desires are always ‘teleologically contaminated’ in the above fashion. In fact, the generation of desire-based mentalistic action explanations can be seen as a two-stage process involving a teleological inferential component (Stage 1) and a mental attributional component (Stage 2). During Stage 1, a teleological explanatory relation is established among three elements: a) a behaviour as means action, b) a future state of reality as goal in relation to which the behaviour is rational, and c) relevant aspects of reality which form background conditions for judging the behaviour as a justifiable means to bring about the end state. Stage 2 involves the further operation of attributing the representation of the (teleologically inferred) future state to the mind of the agent as desire, and, similarly, of attributing the representation of the relevant states of reality as beliefs. In short, even though mentalistic belief-desire explanations of actions are formulated as causal relations between intentional mental states and actions, their inferential structure always involves a teleological (reason-giving) element. 3 The relation between the infant’s teleological stance and mentalistic action explanations What is the nature of the relation between infants’ early ability to interpret behaviour as goal-directed action and the more mature mentalistic action explanations of young children? We see four logical possibilities: (i) they are unrelated, (ii) they are manifestations of the same capacity, (iii) teleological explanations are derived from a causal theory of mind, or (iv) causal mentalistic explanations are extensions of earlier, purely teleological interpretations. We consider these options in turn. 3.1. Teleological and mentalistic action explanations are