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A Puzzle about Pointing

How do infants understand pointing actions?

Explain this in terms of models.

Hypothesis 2: shared intentionality

This is Tomasello et al's hypothesis.
Observe the quotes: I'm doubtful that there is any such thing as shared intentionality, but I have to suspend belief in order to try to work out what their view is.
By the way, this is related to the essay topic on shared intentionality.
Tomasello takes infants' pointing to be based on what he calls shared intentionality.

shared intentionality

‘infant pointing is best understood---on many levels and in many ways---as depending on uniquely human skills and motivations for cooperation and shared intentionality, which enable such things as joint intentions and joint attention in truly collaborative interactions with others (Bratman, 1992; Searle, 1995).’

Tomasello et al (2007, p. 706)

\citep[p.\ 706]{Tomasello:2007fi}
I don't want to pursue this here; I'm just mentioning it because you might want to draw on pointing in your seminar essays.
Instead I want to ask in a simpler way, how should we understand pointing as other non-linguistic forms of communication?
To approach this question, it's helpful to compare and contrast humans with other, nonhuman apes.
Here is a beautifully simple story. Humans are highly cooperative from birth. Being highly cooperative enables them to communicate, linguistically and non-linguistically. Being able to communicate in turn enables them to acquire knowledge of minds, physical objects, numbers and the rest. This is a beautiful story and conceptually simple. Of course the challenge is to get from the story to the details.
But Tomasello doesn't stick with the simple story. Instead ...
There is this additional element, shared intentionality. I don't understand what it is, but Tomasello and his colleagues are extraordinay scientsits so I think it's worth exploring.
That's it for now: all I want to do is highlight that our thinking about pointing is going to connect with questions about shared intentionality.
But why suppose that ‘infant pointing is best understood … is best understood … as depending on … shared intentionality’?
It's goingt to take a while to answer this question ...

Why suppose this?

Hare & Tomasello, 2004

There is a need to contrast understanding action with understanding pointing. After all, there are subjects (chimpanzees) who can comprehend a failed reach but not a pointing action. How does understanding these actions, the failed reach and the pointing action differ? Moll and Tomasello offer a view ...
In this experiment, we contrast failed reaches with pointing ... Hare and Call (\citeyear{hare_chimpanzees_2004}) contrast pointing with a failed reach as two ways of indicating which of two closed containers a reward is in. Chimps can easily interpret a failed reach but are stumped by the point to a closed container. You are the subjects. This is what you saw (two conditions). Your task was to choose the container with the reward. Infants can do this sort of task, it's really easy for them \citep{Behne:2005qh}. (And, incidentally, they distinguish communicative points from similar but non-communicative bodily configurations.) The pictures in the figure stand for what participants, who were chimpanzees, saw. The question was whether participants would be able to work out which of two containers concealed a reward. In the condition depicted in the left panel, participants saw a chimpanzee trying but failing to reach for the correct container. Participants had no problem getting the reward in this case, suggesting that they understood the goal of the failed reach. In the condition depicted in the right panel, a human pointed at the correct container. Participants did not get the reward in this case as often as in the failed reach case, suggesting that they failed to understand the goal of the pointing action. (Actually the apes were above chance in using the point, just better in the failed reach condition. Hare et al comment ;chimpanzees can learn to exploit a pointing cue with some experience, as established by previous research (Povinelli et al. 1997; Call et al. 1998, 2000), and so by the time they engaged in this condition they had learned to use arm extension as a discriminative cue to the food’s location' \citep[p.\ 578]{hare_chimpanzees_2004}.)% \footnote{% The contrast between the two conditions is not due merely to the fact that one involves a human and the other a chimpanzee. Participants were also successful when the failed reach was executed by a human rather than another chimpanzee \citep[][experiment 1]{hare_chimpanzees_2004}. }
\textbf{Note that} chimpanzees do follow the point to a container \citep[see][p.\ 6]{Moll:2007gu}.

‘to understand pointing, the subject needs to understand more than the individual goal-directed behaviour. She needs to understand that by pointing towards a location, the other attempts to communicate to her where a desired object is located’

\citep[p.\ 6]{Moll:2007gu}.

Moll & Tomasello, 2007 p. 6

\subsection{pointing vs linguistic communication}
‘the most fundamental aspects of language that make it such a uniquely powerful form of human cognition and communication---joint attention, reference via perspectives, reference to absent entities, cooperative motives to help and to share, and other embodiments of shared intentionality---are already present in the humble act of infant pointing.’ \citep[p.\ 719]{Tomasello:2007fi}
‘cooperative communication does not depend on language, […] language depends on it.’ \citep[p.\ 720]{Tomasello:2007fi}
‘Pointing may […] represent a key transition, both phylogenetically and ontogenetically, from nonlinguistic to linguistic forms of human communication.’ \citep[p.\ 720]{Tomasello:2007fi}