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Like Knowledge and Like Not Knowledge

I'm sorry to keep repeating this but I want everyone to understand where we are. There are principles of object perception that explain abilities to segment objects, to represent them while temporarily unperceived and to track their interactions. These principles are not known. What is their status?

a problem

Three Questions

1. How do four-month-old infants model physical objects?

2. What is the relation between the model and the infants?

3. What is the relation between the model and the things modelled (physical objects)?

The Simple View answers this question. But the Simple View is incorrect. So we need an alternative answer. And it is difficult to find one because ...

Four-month-olds can act (e.g. look, and reach) for the reason that this object is there.

Four-month-olds cannot believe, nor know, that this object is there.

Uncomplicated Account of Minds and Actions

For any given proposition [There’s a spider behind the book] and any given human [Wy] ...

1. Either Wy believes that there’s a spider behind the book, or she does not.

2. Either Wy can act for the reason that there is, or seems to be, a spider behind the book (where this is her reason for acting), or else she cannot.

3. The first alternatives of (1) and (2) are either both true or both false.

\subsection{Uncomplicated Account of Minds and Actions} For any given proposition [There’s a spider behind the book] and any given human [Wy] ... \begin{enumerate} \item Either Wy believes that there’s a spider behind the book, or she does not. \item Either Wy can act for the reason that there is, or seems to be, a spider behind the book, or else she cannot. \item The first alternatives of (1) and (2) are either both true or both false. \end{enumerate}

generality of the problem

The problem is quite general. It doesn't arise only in the case of knowledge of objects but also in other domains (like knowledge of number and knowledge of mind). And it doesn't arise only from evidence about infants or nonhuman primates; it would also arise if our focus were exclusively on human adults. More on this later. For now, our aim is to better understand the problem as it arises in the case of knowledge of objects.
domainevidence for knowledge in infancyevidence against knowledge
colourcategories used in learning labels & functionsfailure to use colour as a dimension in ‘same as’ judgements
physical objectspatterns of dishabituation and anticipatory lookingunreflected in planned action (may influence online control)
number--""----""--
syntaxanticipatory looking[as adults]
mindsreflected in anticipatory looking, communication, &cnot reflected in judgements about action, desire, ...

knowledge belief representation

One hopeful alternative is to shift from talk about knowlegde to talk about representation. Will this help? Only as a way of describing the problem.
We need to say what we mean by representation. The term is used in a wide variety of ways. As I use it, representation is just a generic term covering knowledge, belief and much else besides.
If we are going to substitute representation for knowledge, we need to characterise what kind of representation we have in mind. The term is tricky. As \citet{Haith:1998aq} says, ‘no concept causes more problems in discussions of infant cognition than that of representation.’

‘no concept causes more problems in discussions of infant cognition than that of representation’

(Haith 1998)

\citep{Haith:1998aq}.
Take a paradigm case of representation.
The subject might not be the agent but some part of it.
That is, we can imagine that some component of an agent, like her perceptual system or motor system, represents things that she herself does not.
(Of course, to make sense of this idea we need to invoke some notion of system.)
The content is what distinguishes one belief from all others, or one desire from all others.
The content is also what determines whether a belief is true or false, and whether a desire is satisfied or unsatisfied.
There are two main tasks in constructing a theory of mental states.
The first task is to characterise the different attitudes.
This typically involves specifying their distinctive functional and normative roles.
The second task is to find a scheme for specifying the contents of mental states.
The second task is to find a scheme for specifying the contents of mental states.
Usually this is done with propositions.
But what are propositions?
Propositions are abstract objects like numbers.
They have more mystique than numbers, but, like numbers, they are abstract objects that can be constructed using sets plus a few other basic ingredients such as objects, properties and possible worlds.
So that was some quick background on representation.
Note that the issue of representation comes up twice for us.
There is a question about whether the principles of object perception are represented.
And there is a question about whether objects, their locations, properties, and interactions are represented.
The problem raised by the discrepancy between looking and acting is a problem for two claims: (i) the simple view (the principles of object perception are knowledge &c); and also (ii) the claim that the representations of objects which derive from the principles of object perception are knowledge states.

knowledge belief representation

So to say that we don't know the principles of object perception but only represent them doesn't tell us much. This is a step in the right direction. But it tells us that we represent them without knowing them.
What we need if we're to have an explanatory answer to Q2a is to know positively how we do represent the principles of object perception --- subject, attitude and content. We need to characterise a form of representation that is like knowledge but not like knowledge.
Your handbag is bluging, and when you swing it at me something really hard hits me.
It must be full of rocks.
Except it can't be because you are not strong enough to lift such a big bag full of rocks.
In that case, it must be wrocks not rocks.
A wrock is just like a rock except that it lacks mass.
Compare: this representation is just like knowledge except that it doesn't guide action; this process is just like inference except that it lacks the normative aspects of inference.

the parable of the wrock

strength (Munakata 2001)

A different way to duck Davidson’s Challenge has been proposed by \citeauthor{Munakata:2001ch} (\citeyear{Munakata:2001ch}; see also \citealp{munakata:1997_rethinking}). She suggests that knowledge can be ‘graded’: some knowledge states are ‘stronger’ while others are ‘weaker’. She also holds that weaker knowledge states can drive looking time behaviours but not control purposive action. This allows her to hold that four-month-olds know principles about objects generally and facts about particular objects, just as adults do. So on this view infants’ representations of objects are not different in kind from adults’ knowledge of facts about particular physical objects. % \citep{shinskey:2010_something} specify that the graded representations idea is supposed to be an alternative to postulating core knowledge.
The idea that knowledge can be graded is initially attractive. It appears to avoid the incorrect predictions of the Simple View, yet it does not require meeting Davidson’s Challenge and identify things in between mindless behaviour and knowledge or belief. But this idea also faces a challenge. Talk about ‘strength’ in this context needs to be anchored in a theory of representation. When talking about a radio signal, a notion of strength can be defined in terms of physical properties of waves. In this case it is possible to specify what signal strength amounts to, and it is clear that signals of varying strength can all carry the same message. But what does strength amount to in the case of a mental representation or knowledge state?
Without an answer to this question, invoking graded representations will not explain anything. It amounts merely to retrospectively postulating a novel aspect of representation to characterise findings about what four-month-olds can and can’t do.
To see the force of this challenge, consider that proponents of graded knowledge hold that weaker representations can guide many looking behaviours whereas manual search behaviours generally require stronger representations. Why is it this way around? Why is a stronger representation is needed for manually searching than for looking? Until we can answer this question, postulating graded knowledge will not explain the developmental puzzles about knowledge of objects.
The idea might well make sense if we were talking about neural representations.
But here we aren't. Let's not introduce radically new ideas about representation unless we really have to.
(By the way, \citet{Munakata:2001ch} is a nice review of dissociations, not only developmental dissociations.)

‘if you want to describe what is going on in the head of the child when it has a few words which it utters in appropriate situations, you will fail for lack of the right sort of words of your own.

‘We have many vocabularies for describing nature when we regard it as mindless, and we have a mentalistic vocabulary for describing thought and intentional action; what we lack is a way of describing what is in between

(Davidson 1999, p. 11)

Recall what Davidson said: we need a way of describing what is in between thought and mindless nature. This is the challenge presented to us by the failure of the Simple View.