Syntax / Innateness

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So far we have considered examples of core knowledge. But we have ignored a paradigm case, one which has inspired much work on this topic (although it is not a case Spelke or Carey would recognize! *todo: stress throughout) ...

core knowledge of

physical objects
[colour]
mental states
action
number
...

Human adults have extensive knowledge of the syntax of their languages, as illustrated by, for example, their abilities to detect grammatical and ungramatical sentences which they have never heard before, independently of their meanings. To adapt a famous example from Chomsky, ...

The turnip of shapely knowing isn't yet buttressed by death.
*The buttressed turnip shapely knowing yet isn't of by death.

We need to task two questions.

core knowledge of syntax is innate (?)

First, what is this thing, syntax, which is known?

This thing they know, the syntax, isn't plausibly just a list of which sentences are grammatical.

Because people can make judgements about arbitrarily long, entirely novel sentences.

Rather, the thing known must be something that enables people to make judgements about sentences.

We might think of it roughly as a theory of syntax.

It's like a theory in this sense: knowledge of it enables you to make judgements about the grammaticality of arbitrary sentences.

The second question is, Is it *knowledge* we have syntax or something else?

There's something interesting.

The knowledge can be revealed indirectly, by asking people about whether particular sentences are grammatical.

But people can't say anything about how they know the sentence is grammatical.

It's like perceiving the shape of something: there isn't much to say about how you know.

So the theory of syntax isn't something we can discover by introspection:

we have to *rediscover* it from scratch by investigating people's linguistic abilities.

Knowledge of syntax therefore seems to have some of the features associated with core knowledge.

First, it is domain-specific.

Second, it is inaccessible. That is, it can't guide arbitrary actions.

In what follows I want to suggest that syntax provides a paradigm case for thinking about core knowledge.

In addition, I want to use the case of syntax for thinking about the question, What is innate in humans?

I was astonished how many people considered this question in the unassessed essay, some people seem really fascinated by it.

But almost no one discussed the case of syntax in depth. If you're going to talk about innateness, you really need to know a little bit about syntax.

So I'm also going to provide you with that understanding.

Consider a phrase like 'the red ball'.

What is the syntactic structure of this noun phrase?

In principle there are two possibilities.

the red ball

Lidz et al (2003)

How can we decide between these?

Is the syntactic structure of ‘the red ball’ (a) flat or (b) hierachical?

\begin{center}

\includegraphics[scale=0.25]{../www.slides/src/raw/img/lidz_2003_fig0.neg.png}

\end{center}

\begin{center} from \citealp{lidz:2003_what} \end{center}

\begin{enumerate}

\item ‘red ball’ is a constituent on (b) but not on (a)
\item anaphoric pronouns can only refer to constituents
\item In the sentence ‘I’ll play with this red ball and you can play with that one.’, the word ‘one’ is an anaphoric prononun that refers to ‘red ball’ (not just ball). \citep{lidz:2003_what,lidz:2004_reaffirming}.

\end{enumerate}

What I've just shown you is, in effect, how we can decide whihc way an adult human understands a phrase like 'the red ball'.

We can discover this by finding out how they understand a sentence like 'I’ll play with this red ball and you can play with that one.'.

But how could we do this with infants who are incapable of discussing sentences with us?

infants?

Here's how the experiment works (see \citealp{lidz:2003_what}) ...

The experiment starts with a background assumption:

‘The assumption in the preferential looking task is that infants prefer to look at an image that matches the linguistic stimulus, if one is available’ \citep{lidz:2003_what}.

So the key question was whether infants would look more at the yellow bottle (which is familiar) or the blue bottle (which is novel).

If they think 'one' refers to 'bottle', we'd expect them to look longer at the blue bottle;

and conversely if they think one refers to 'yellow bottle', then they're being asked whether they see another yellow bottle.

And, as always, we need a control condition to check that infants aren't looking in the ways predicted irrespective of the manipulation.

Lidz et al (2003)

And here's what they found ...

Lidz et al (2003, figure 1)

Look, a yellow bottle!	control: What do you see now? test: Do you see another one?
[yellow bottle]	[yellow bottle]	[blue bottle]

What can we conclude so far?

From 18 months of age or earlier, infants represent the syntax of noun phrases in much the way adults do.

So there is core knowledge of syntax ... or is there?

Core knowledge is often characterised as innate.

I think this is a mistake (more about this later), but many of you do not.

But are these representations innate?

How could we tell whether these representations are innate?

What do we mean by innate here?

The easy answer is: not learned.

But I think there's a more interesting way to approach understanding what 'innate' means.

Quite a few people pointed out that there isn't agreement on what innateness is.

But this is not very interesting by itself because there's disagreement about most things and potential causes of disagreement include ignorance and stupidity.

It's also important that the mere fact that a single term is used with multiple meanings isn't an objection to anyone.

As philosophers, some of you are tempted to catalogue different possible notions of innateness.

I encourage you to resist this temptation; if you want to collect something, pick something useful like banknotes.

There's a much better way to approach things.

Let's see what kind of findings are, or would be, taken to show that something is innate.

We can use these to constrain our thinking about innateness.

We will say: assuming that this is a valid argument that X is innate, what could innateness be?

Aside: we have too approach science as radical interpreters ...

How does radical interpretation work?

Interpretation is hard because there are two factors: truth and meaning.

The proposal Davidson makes is that we assume truth and infer meaning.

I'm recommending a similar strategy.

We take for granted that this argument establishes that X is innate; we then ask what innateness could be given that this is so.

‘All understanding of the speech of another involves radical interpretation’

Davidson 1973, p. 125

\citep[p.\ 125]{Davidson:1973jx}

\subsection{Poverty of stimulus arguments}

The best argument for innateness is the poverty of stimulus argument.

We need to step back and understand how poverty of stimulus arguments work.

Here I'm following \citet{pullum:2002_empirical}, but I'm simplifying their presentation.

How do poverty of stimulus arguments work? See \citet{pullum:2002_empirical}.

First think of them in schematic terms ...

Poverty of stimulus argument

\begin{enumerate}

\item
Human infants acquire X.
\item
To acquire X by data-driven learning you'd need this Crucial Evidence.
\item
But infants lack this Crucial Evidence for X.
\item
So human infants do not acquire X by data-driven learning.
\item
But all acquisition is either data-driven or innately-primed learning.
\item
So human infants acquire X by innately-primed learning .

\end{enumerate}

compare Pullum & Scholz 2002, p. 18

This is a good structure; you can use it in all sorts of cases, including the one about chicks' object permanence.

Now fill in the details ...

In our case, X is knowledge of the syntactic structure of noun phrases. (Caution: this is a simplification; see\citet[p,\ 158]{lidz:2004_reaffirming}).)

This is what the Lidz et al experiment showed.

Note that no one takes this to be evidence for innateness by itself.

What is the crucial evidence infants would need to learn the syntactic structure of noun phrases?

This is actually really hard to determine, and an on-going source of debate I think.

But roughly speaking it's utterances where the structure matters for the meaning, utterances like 'You play with this red ball and I'll play with that one'.

\citet{lidz:2003_what} establish this by analysing a large corpus (collection) of conversation involving infants.

What can we infer about innateness from this argument?

First, think about what is innate. The fact that knowledge of X is acquired other than by data-driven learning doesn't mean that X is not innate; it just means that something which enables you to learn this is.

Second, think about the function assigned to innateness. That which is innate is supposed to stand in for having the crucial evidence.

This, I think, is the key to thinking about what we *ought* to mean by innateness.

So attributes like being genetically specified are extraneous---they may be typical features of innate things, but they aren't central to the notion.

By contrast, that what is innate is not learned must be constitutive (otherwise that which is innate couldn't stand in for having the crucial evidence)

Contrary to what many philosophers (including Stich and Fodor) will tell you ...

‘the APS [argument from the poverty of stimulus] still awaits even a single good supporting example’

Pullum & Scholz 2002, p. 47

\citep[p.\ 47]{pullum:2002_empirical}

But they wrote this before \citet{lidz:2003_what} came out.

What is innate in humans?

I asked you this question, but what do I think?

I'd approach it by distinguishing two sub-questions (the second of which has two sub-sub-questions)

**todo: Stress other conceptions and arguments good; start with a project from \citet{spelke:2012_core} or from \citet{haun:2010_origins} and you reach a different point!

What evidence is there?
What does the evidence show is innate?

Type: knowledge, core knowledge, modules, concepts, abilities, dispositions ...
Content: e.g. universal grammar, principles of object perception, minimal theory of mind ...

Arguments from the poverty of stimulus are the best way to establish innateness.

The argument concerning syntax we've just been discussing is quite convincing, although if you follow up on the references given in the handout you'll see it's not decisive (as always).

For things other than knowlegde of syntax, the evidence concerning humans is far less clear.

There are, however, quite good cases in nonhuman animals, as many of you know.

So it's not unreasonable to conjecture that learning in the several domains where infants appear to know things early in their first year is innately-primed rather than entirely data-driven.

But, one or two cases aside, there's enough evidence to rule out the converse conjecture.

I don't think what is innate is knowledge, nor do I think it's concepts.

But I think there's a good chance that modules are innate (and therefore core knowledge if I'm right to suppose that 'core knowledge' is a term for the fundamental principles describing the operation of a module).

On content: I think quite a lot is known about the modules thanks to detailed tests that have little to do directly with controversy about inateness.

Why care about whether something is innate? (This isn't suppose to be dismissive.)

so what?

Here are two reasons why I think we shouldn't worry too much about innateness in trying to understand the origins of mind.

(1) The question about innateness concerns the first transition, whereas I think the second should be our focus (for pragmatic reasons: there's more research).

(2) Discoveries about innately-primed learning make only a relatively modest contribution to understanding the emergence of core knowledge in development. So even when we consider the first transition, it's not obvious that discoveries about innateness are very illuminating, for all their pop-science appeal.

Metaphor: we find a cake in the ruins of Pompeii preserved for a couple of thousand years. We're trying to reconstruct its manufacture.

Its good if someone obsesses about where the eggs came from. Did the baker have her own chickens or did she get them from a friend?

But knowing where the eggs came from is unlikely to be critical to understanding how the cake was manufactured.

We're not finished when we know where the eggs came from, and we're not doomed to fail if we don't know.

So let me put the innateness issue aside and get back to what I think matters most ...

Conclusion

Adults have inaccessible, domain-specific representations concerning the syntax of natural languages.
So do infants (from 18 months of age or earlier, well before they can use the syntax in production).
These representations plausibly enable understanding and play a key role in the development of abilities to communicate with language.
These representations are a paradigm case of core knowledge.

This paradigm allows me to highlight something about core knowledge.

I would be a mistake to suppose that there is some core knowledge which later becomes knowledge proper --- e.g. the fact that barriers stop solid objects is first core knowledge then later knowledge.

The content of the core knowledge is a theory of syntax (let's say).

Or, in another case, the content of core knowledge is some principles of object perception.

These are things that human adults do not typically know at all, at least not in the sense that they could state the principles.

So core knowledge enables us to do things, like anticipate where unseen objects will re-appear or communicate with words.

It doesn't seem to be linked directly to the acquisition of concepts.