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Pure Goal Tracking

An account of pure goal ascription is an account of how you could in principle infer facts about the goals to which actions are directed from facts about joint displacements, bodily configurations and their effects (e.g. sounds). Such an account is a computational theory of pure goal ascription.

pure goal tracking

Infer The Goals from The Evidence

The Goals: facts which goals particular actions are directed to...

The Evidence: facts about events and states of affairs that could be known without knowing which goals any particular actions are directed to, nor any facts about particular mental states ...

Be sure about the topic

goal ascription    goal tracking

Two forms of goal ascription, representational and functional (\citealp{gallese:2011_what}). In \emph{representational goal ascription}, three things must be represented: an action, an outcome and the relation between this outcome and the action in virtue of which the outcome is a goal of the action. % jacob:2012_sharing: ‘Ascribing a goal to an agent consists in forming a belief (or judgment) about an agent that he or she has a goal or is performing some goal-directed action.’ In \emph{functional goal ascription}, the relation between action and outcome is captured without being represented. To say that this relation is \emph{captured} is to say that there is a process which ensures that the outcome represented is a goal of the action.
Motor representations cannot suffice for representational goal ascription. It is true that, in someone observing an action there can be motor representations of outcomes which, non accidentally, are the goals of the observed action. But this is not enough. There would have to be, in addition, a motor representation of an intention, or of a motor representation or of some other goal-state, or of a function. But there are no such motor representations.

Goal tracking matters for

identifying mental states

Because ascriptions of mental states are based on observed behaviours.

identifying effects of actions

predicting when an event of interest will occur

learning how to do things

Our primary concern here with behaviour reading is as a potential basis for abilities to track others’ mental states without representing them. But behaviour reading is plausibly important in other ways. In mindreaders, behaviour reading is thought to be useful or even necessary for identifying intentions and other mental states (\citealp[p.~861]{Newtson:1977dw}; \citealp[p.~708]{Baldwin:2001rn}). Behaviour reading may also matter for efficiently representing events \citep{Kurby:2008bk}, identifing the likely effects of actions \citep{Byrne:1999jk}, predicting when an event likely to be of interest will occur \citep[p.~121]{Swallow:2008cf}, and learning through observation how to do things \citep{Byrne:2003wx}. And of course a special case of pure behaviour reading, ‘speech perception’, underpins communication by language in humans.
Start with a case in which behaviour reading is clearly involved. I take Byrne’s study to demonstrate that chimps are capable of sophisticated behaviour reading. But how might they represent behaviours?
The procedure for preparing a nettle to eat while avoiding contact with its stings is shown in \vref{fig:byrne_2003_fig1}. It involves multiple steps. Some steps may be repeated varying numbers of times, and not all steps occur in every case. The fact that gorillas can learn this and other procedures for acquiring and preparing food by observing others’ behaviour suggests that they have sophisticated behaviour reading abilities \citep[p.~513]{Byrne:2003wx}. If we understood the nature of these behaviour reading abilities and their limits, we might be better able to understand their abilities to track mental states too.

Byrne 2003, figure 1

‘great apes [are] able to acquire complex and elaborate local traditions of food acquisition, some of them involving tool use’ \citep[p~513]{Byrne:2003wx}
So even quite sophisticated behaviour reading is possible without any reliance on communication by language. We can therefore think of behaviour reading as foundational for any kind of radical interpretation.
[background] ‘Nettles, Laportea alatipes, are an important food of mountain gorillas in Rwanda (Watts 1984), rich in protein and low in secondary compounds and structural carbohydrate (Waterman et al. 1983). Unfortunately for the gorillas, this plant is 'defended' by powerful stinging hairs, especially dense on the stem, petioles and leaf-edges. All gorillas in the local population process nettles in broadly the same way, a technique that minimizes contact of sting- ing hairs with their hands and lips (Byrne & Byrne 1991; figure 1). A series of small transformations is made to plant material: stripping leaves off stems, accumulating larger bundles of leaves, detachment of petioles, picking out unwanted debris, and finally folding a package of leaf blades within a single leaf before ingestion. The means by which each small change is made are idiosyncratic and variable with context (Byrne & Byrne 1993), thus presum- ably best learned by individual experience. However, the overall sequence of five discrete stages in the process is standardized and appears to be essential for efficiency (Byrne et al. 2001a).’ \citep[pp.~531--2]{Byrne:2003wx}
‘Like other complex feeding tasks in great apes, preparing nettles is a hierarchically organized skill, showing considerable flexibility: stages that are occasionally unnecessary are omitted, and sections of the process (of one or several ordered stages) are often repeated iteratively to a criterion apparently based on an adequate size of food bundle (Byrne & Russon 1998).’ \citep[pp.~532]{Byrne:2003wx}