A Puzzle about Pointing

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A Puzzle about Pointing

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Our overall project is to understand something about the emergence of knowledge of minds, objects, colours and the rest in human development. My proposal is that we have to take two factors into account. One is core knowledge, the other is social interaction. Our current project is to understand where abilities to communicate fit into this picture---to understand, that is, what role they might play in explaining how humans come to know things.

Increasingly sophisticated forms of social interaction continue to combine with core knowledge to yield increasingly sophisticated forms of cognition, resulting in konwledge itself.

Liszkowski et al 2004, figure 2

Infants spontaneously point from around 12 months.

Here is a situation in which a child is playing at her table. Then something appears from behind a sheet. The infant spontaneously points at it.

Which

model

of communication?

A model of communication is just some description of a way communication might, in principle, work.

The *infant’s model* of communication is the way the world would have to be in order for infants’ communication to be optimal.

model of communication block--slab model Gricean model

model 1: block--slab (pure use)

‘Let us imagine a language for which the description given by Augustine is right. [...]

A is building with building-stones: there are blocks, pillars, slabs and beams.

B has to pass the stones, and that in the order in which A needs them.

For this purpose they use a language consisting of the words ‘block’, ‘pillar’, ‘slab’, ‘beam’.

A calls them out; B brings the stone which he has learnt to bring at such-and-such a call.’

Wittgenstein (1953, §2)

Can we think of infant pointing on this model, just as a bit more sophisticated in that the pointing gesture picks out different objects on different occasions?

What are the limits of this picture? (a) there is a fixed thing that people do in response to pointing. (b) the context of the activity in which the pointing occurs is fixed (it’s building).

The _block--slab_ model of infant pointing (Wittgenstein, 1953, p. compare][§2): (a) the activity occurs in a fixed context (e.g. buliding) and (b) there is a fixed thing to be done in response to a point.

From around 11 or 12 months of age, humans spontaneously use pointing to ...

request
inform
(Liszkowski, Carpenter, & Tomasello, 2008, p. Exp. 2)
initiate joint engagement (‘Wow! That!’)
(Liszkowski, Carpenter, Striano, & Tomasello, 2006)
obtain information
(Begus & Southgate, 2012; Lucca & Wilbourn, 2018)

overview: (Tomasello, Carpenter, & Liszkowski, 2007)

Let's have a look at the evidence for informative pointing.

Liszkowski et al 2008, figure 3

Liszkowski et al 2008, figure 5

Subjects are 12-month olds. Fig. 5. Experiment 2. Mean proportion of trials with a point in the experimental (E is ignorant) and control (E is knowledgeable) conditions.

From around 11 or 12 months of age, humans spontaneously use pointing to ...

request
inform
(Liszkowski, Carpenter, & Tomasello, 2008, p. Exp. 2)
initiate joint engagement (‘Wow! That!’)
(Liszkowski, Carpenter, Striano, & Tomasello, 2006)
obtain information
(Begus & Southgate, 2012; Lucca & Wilbourn, 2018)

overview: (Tomasello, Carpenter, & Liszkowski, 2007)

Why is this significant? Because it implies that infant pointing is not just a matter of getting you to do things for the infant, nor of getting you to do things with the infant. Instead it can be used where the infant has no expectation that you will do anything with or for the infant. And this matters because it constrains how an infant could understand pointing.

why not?

model 1: block--slab (pure use)

We said eariler that the _block--slab_ model of infant pointing (Wittgenstein, 1953, p. compare][§2): (a) the activity occurs in a fixed context (e.g. buliding) and (b) there is a fixed thing to be done in response to a point.

The findings are therefore enough to rule it out already.

But couldn’t we extend the block--slab model just slightly so that each word had three uses instead of one? And couldn’t we allow that those who adopt it might be sensitive to others’ informational needs in some way?

We have not yet seen grounds for a major departure from block-slab, I think.

communicative purpose vs extra-communicative purpose

Essence of any pure use model (like block--slab) is this: On the block--slab model there is no need at all to distinguish communicative and extra-communicative purposes.

Each word has a fixed use (or uses) and that is all there is to say about it. It is because adults’ pointing can serve an open-ended range of ends that we have to distinguish communicative and extra-communicative purposes. As we will see, this is a source of theoretical complexity.

evidence for context sensitivity: Liebal, Behne, Carpenter, & Tomasello (2009, p. Exp. 1)

model 2 : Gricean intentions ...

Will build up to 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 (Behne, Carpenter, & Tomasello, 2005). (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' (Hare & Tomasello, 2004, p. \ 578).)% \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 (Hare & Tomasello, 2004, p. ][experiment 1). }

**Note that** chimpanzees do follow the point to a container (Moll & Tomasello, 2007, p. see][p.\ 6).

‘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’

(Moll & Tomasello, 2007, p. \ 6).

Moll & Tomasello, 2007 p. 6

what is an attempt to communicate?

### 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.’ (Tomasello et al., 2007, p. \ 719)

‘cooperative communication does not depend on language, […] language depends on it.’ (Tomasello et al., 2007, p. \ 720)

‘Pointing may […] represent a key transition, both phylogenetically and ontogenetically, from nonlinguistic to linguistic forms of human communication.’ (Tomasello et al., 2007, p. \ 720)

What is an attempt to communicate?

communicative purpose vs extra-communicative purposes

recall we already mentioned this

Step 1: It’s an action with a communicative purpose.

Step 1: attempt to communicate is action performed with a communicative purposes.

It’s an action done with an intention to provide someone with evidence of an intention with the further intention of thereby fulfilling that intention

(compare Grice, 1989 chapter 14)

Hare & Tomasello, 2004

Moll & Tomasello, 2007 p. 6

Let’s try to apply this idea to our pointing study ...

What is the confederate doing if she's pointing to inform?

An action done with an intention to provide someone with evidence of an intention with the further intention of thereby fulfilling that intention

(compare Grice, 1989 chapter 14)

Recall the comprehension of pointing case; what is the confederate doing if she's pointing to inform?

The confederate means something in pointing at the left box if she intends:

#. that you open the left box;
#. that you recognize that she intends (1), that you open the left box; and
#. that your recognition that she intends (1) will be among your reasons for opening the left box.

(Compare Grice, 1967 p. 151; Neale, 1992 p. 544)

So to mean something by pointing, you have to have to have an intention about my recognition of an intention of yours concerning my reasons.

An inconsistent tetrad #. 11- or 12-month-old infants produce and comprehend declarative pointing gestures. #. Producing or comprehending pointing gestures involves understanding communicative actions. #. A communicative action is an action done with an intention to provide someone with evidence of an intention with the further intention of thereby fulfilling that intention. #. Pointing facilitates the developmental emergence of sophisticated cognitive abilities including mindreading

Inconsistent tetrad

1. 11- or 12-month-old infants produce and comprehend declarative pointing gestures.

This is what we have evidence for

2. Producing or comprehending pointing gestures involves understanding communicative actions.

This is the rejection of the ‘block-slab’ model of communication

3. A communicative action is an action done with an intention to provide someone with evidence of an intention with the further intention of thereby fulfilling that intention.

This is the theory I take Tomasello & Moll to endorse (although they are not very explicit about it, it’s based on their use of the term ‘shared intentionality’).

4. Pointing facilitates the developmental emergence of sophisticated cognitive abilities including mindreading.

Which claim should we reject?

I’d like to be able to reject (3). But to do that of course we have to supply an alternative account of what a communicative action is, one that doesn’t involve appeal to intention.

Is model 1 (block--slab) too impoverished? Why (not)?

How strong is the case for model 2 (Gricean intentions)?

Moll & Tomasello (2007); Csibra (2010)

Are there any alternatives (i.e. model 3)?

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A Puzzle about Pointing

A Puzzle about Pointing

[email protected]

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