In Philosophy, it’s useful to sometimes step back and ask yourself: ‘Wait, what exactly are we talking about? Can I get some clear examples of the thing I’m trying to understand?’

This lecture:

1. Scene setting, filling in some historical information, and honing in on the target of inquiry...
2. Brief characterization of so-called “eliminative materialism”

Characterizing the Target Phenomena......in phenomenal terms (Unit 2): ‘feels’, ‘sensation’, ‘experience’, ‘hurts’, etc.

...in cognitive terms (Unit 3): ‘think’, ‘notice’, ‘wonder’, ‘consider’, ‘decide’, ‘goals’, ‘want’, ‘believes’, etc.

• Note: In everyday thought/talk about the mental, we often mix and match ideas/terms from these two lists. And some terms (e.g. ‘see’, ‘perceive’, ‘sense’, ‘desires’, ‘hopes’) maybe mean different things, depending on the context in which the term in used.
• (For the canonical characterization of this division, see Chapter 1 of Chalmers’ “The Conscious Mind”.)

“Folk Psychology”In everyday thought/talk, we seem to use a basic belief/desire/rationality model for understanding one another and for predicting each other’s behavior.

• “Each of us understands others, as well as we do, because we share a tacit command of an integrated body of lore concerning the law-like relations holding among external circumstances, internal states, and overt behavior. Given its nature and functions, this body of lore may quite aptly be called "folk psychology.”

“The Propositional Attitudes”When philosophers of mind and language have tried to unpack and analyze our pre-theroetical target, they often focus on something they call propositions: abstract ‘claims’/’sentences’/‘ideas’ that get expressed in our cognitive attitudes.

• Importantly, propositions (according to many philosophers) express ways the world may or may not be. You can think of them as ‘statements’ that are potentially true/false.

Cognitive attitudes...

• Believe that...
• Desire that...
• Imagine that...
• Think that...
• Hope that....
• (many more...)

The So-Called ‘Cognitive Revolution’The so-called “computer model of the mind” can be thought of as directly tied to the so-called ‘cognitive revolution’ in psychology and it’s neighbors (mainly CS/AI and philosophy).

• Psychology: The triumph of the 'cognitivists' over ‘methodological behaviorists’ in psychology (cf. Noam Chomsky’s ‘poverty of the stimulus’ argument)
• CS: The rise of earnest attempts at ‘strong AI’
• Philosophy: The rise of science-loving functionalism in philosophy of mind.

To some academics, this had the feeling of “the end of history", with ‘the computer model of the mind’ as the inevitable, final stop in a long march towards understanding the mind.

Viva La Revolution?But it’s never that simple...

• In psychology: rise of social psychology, ‘cognitive biases’, and the emergance of alternatives to the standard computer model (e.g. parallel distributed processing.)
• In CS/AI: AI Winter!
• In philosophy: although functionalism became popular, it got attacked from all sides, and most self-ascribed functionalists have thought that they can’t really answer their opponents

(Aside: I think the functionalists gave up too easy and can win the war with another sustained attempt to build out the theory...)

Gallistel on Representation and ComputationOne key idea that I hope is brought out by the Gallistel reading: linking the problem of representation/intentionality to the problem of cognition/intelligence. A ton is packed into the abstract:

“A mental representation is a system of symbols isomorphic to some aspect of the environment, used to make behavior-generating decisions that anticipate events and relations in that environment. A representational system has the following components: symbols, which refer to aspects of the environment, symbol processing operations, which generate symbols representing behaviorally required information about the environment by transforming and combining other symbols, representing computationally related information, sensing and measuring processes, which relate the symbolic variables to the aspects of the world to which they refer, and decision processes, which translate decision variables into observable actions. From a behaviorist perspective, mental representations do not exist and cannot be the focus of a scientfic psychology. From a cognitivist perspective, psychology is the study of mental representations, how they are computed and how they affect behavior.”

The Upshot: Representations emerge in nature when computation emerges in nature. Representations are then to be understood as embedded in natural systems, which implement various cognitive strategies. In short, the cognitive goals of natural cognitive systems are either: a) explanatorily prior to representations, or b) conceptually linked to the nature of cognition.

“Although mental representations are central to prescientific folk psychology, folk psychology does not provide a rigorous definition of representation, any more than folk physics provides a rigorous definition of mass and energy. Although mental representations are central to prescientific folk psychology, folk psychology does not provide a rigorous definition of representation, any more than folk physics provides a rigorous definition of mass and energy.”

“A representation, mental or otherwise, is a system of symbols. The system of symbols is isomorphic to another system (the represented system) so that conclusions drawn through the processing of the symbols in the representing system constitute valid inferences about the represented system.”

Cognitive states are often/usually (?) representational states, and so any story about cognition ought to be accompanied by a story about representation. Otherwise, you wouldn’t be able to distinguish, say, the belief that it is raining outside from the belief that the Taj Mahal is white. There’s a cognitive difference to be accounted for here in terms of a difference in representational content.

My preferred framing...The problem of consciousness: What makes human brains (or anything else) ‘give rise’ to phenomenal experience?

The problem of cognition/rationality/intelligence: What is it about a cognitive system that makes it truly think?

The problem of representation/intentionality: What is it about a cognitive system that makes its internal states represent ‘the world out there’?

Perhaps the problem of cognition and the problem of representation, in order to be properly appreciated, have to be handled separately. But they might also be the very same problem ‘deep down’. There is nothing like ‘expert consensus’ on the issue.

As I read Churchland and Dennett, they both think that cognition and representation are connected in some deep and important way...

Churchland will say: Yes, representation-talk is tied to cognition-talk. But these are bad, confused ways of talking! Drop it!

• The Big Problem: has a kind of self-undermining quality to it, since Churchland seems to be saying both “You can understand these sentences as expressing true thoughts” and “Sentences which rely (either implicitly or explicitly) on [the rational agent model] are, strictly speaking, false, because rational agents don’t exist.”

Dennett will say: Must we choose between realism and anti-realism? Can’t we just say that different ways of thinking about the same underlying thing are useful in different ways, and leave it at that?

• The Big Problem: Dennett seems to want to have his cake and eat it too!

Churchland’s Eliminative Materialism[illusionism : consciousness :: eliminative materialism : cognition/representation]

“Eliminative materialism is the thesis that our common-sense conception of psychological phenomena constitutes a radically false theory”

Folk psychology represents a kind of ‘common sense theory’ which advanced neurobiology/psychology will/should completely replace.

And so folk psychology, according to Churchland, should be treated like any other ‘common sense' theory that gets thrown away once we develop a more sophisticated theory.

“...the semantics of the terms in our familiar mentalistic vocabulary is to be understood in the same manner as the semantics of theoretical terms generally: the meaning of any theoretical term is fixed or constituted by the network of laws in which it figures.”

“Recall the view that space has a preferred direction in which all things fall; that weight is an intrinsic feature of a body; that a force-free moving object will promptly return to rest; that the sphere of the heavens turns daily; and so on.”

Upshot: While we may still talk/think in terms of ‘beliefs’ and ‘desires’ and ‘rationality’, such talk is, strictly speaking, false.