Sunday, June 15, 2014

The Philosopher's Zone - Mind the Brain

This is last week's episode of The Philosopher's Zone podcast, with guest Daivd Papineau, professor at King's College in London. Papineau has worked in metaphysics, epistemology, and the philosophies of science, mind, and mathematics. His overall stance is naturalist and realist. He is one of the originators of the teleosemantic theory of mental representation, a solution to the problem of intentionality which derives the intentional content of our beliefs from their biological purpose. He is also a defender of the a posteriori physicalist solution to the mind-body problem.

Here is a lengthy explanation of teleosemantic theories in philosophy from the Stanford Encyclopedia of Philosophy:
What all teleological (or “teleosemantic”) theories of mental content have in common is the idea that psycho-semantic norms are ultimately derivable from functional norms. Beyond saying this, it is hard to give a neat definition of the group of theories that qualify.

Consider, for instance, some theories that are clearly intended as alternatives to teleosemantics, such as Fodor's (1990b) asymmetric dependency theory or theories that appeal to convergence under ideal epistemic conditions (see Rey 1997 for an outline). Elaboration of these theories is beyond the scope of this entry but we can note that they both seem to need a notion of normal or proper functioning. Fodor's theory adverts to the “intact” perceiver and thinker. Presumably this is someone whose perceptual and cognitive systems are functioning properly (this is covered under the ceterus paribus part of the laws to which Fodor's theory refers). The idea of convergence under ideal epistemic conditions also involves a notion of normal functioning, for epistemic conditions are not ideal if perceivers and thinkers are abnormal in certain respects, such as if they are blind or psychotic. If normal or proper functioning is analyzed in terms of an etiological theory, which says that a system functions normally or properly only if all of its parts possess the dispositions for which they were selected, then these theories would qualify as teleological theories of mental content under the characterization provided in the first paragraph of this section. Those who propose these theories might reject an etiological theory of functions, but they need some analysis of them. There could anyway be etiological or teleological versions of theories of this sort.

An appeal to teleological functions can also be combined with a variety of other ideas about how content is determined. For example, there can be both isomorphic and informational versions of teleosemantics. In the former case, the proposal might be that the relevant isomorphism is one that cognitive systems were adapted to exploit. An alternative idea is that the isomorphism does not need to be specified given that the targets of representations are determined by teleological functions. This appears to be the view of Cummins (1996, see esp. p.120) although Cummins is generally critical of teleological functions in biology. A teleological version of an informational theory is given when content is said to depend on information carrying, storing or processing functions of mechanisms. The relevant notion of information is variously defined but (roughly speaking) a type of state (event, etc.) is said to carry natural information about some other state (event, etc.) when it is caused by it or corresponds to it. 

It is sometimes said that the role of functions in a teleological theory of content is to explain how error is possible, rather than to explain how content is determined, but the two go hand in hand. To see this, it helps to start with the crude causal theory of content and to see how the problem of error arises for it. According to the crude causal theory, a mental representation represents whatever causes representations of the type; Rs represent Cs if and only if Cs cause Rs. One problem with this simple proposal is its failure to provide for the possibility of misrepresentation, as Fodor (1987, 101–104) points out. To see the problem, recall the occasion on which crumpled paper is seen as a cat. The crude causal theory does not permit this characterization of the event because, if crumpled paper caused a tokening of CAT then crumpled paper is in the extension of CAT, according to the crude causal theory. Since cats also sometimes cause CATs, cats are in the extension too. However, the problem is that crumpled paper is included in the extension as soon as it causes a CAT to be tokened and so, on this theory, there is no logical space for the possibility of error since candidate errors are transformed into non-errors by their very occurrence. Note that the problem is simultaneously one of ruling in the right causes without also ruling in the wrong ones. CAT cannot have the content cat unless non-cats (including crumpled paper) are excluded from its content. So explaining how content is determined and how the possibility of error are accommodated are not separate tasks.

The error problem is an aspect of what (after Fodor) is often called “the disjunction problem.” With respect to the crude causal theory, the name applies because the theory entails disjunctive contents when it should not. For example, it entails that CATs have the content cats or crumpled paper in the case just considered. The disjunction problem is larger than the problem of error, however, because it is not only in cases of error that mental representations are caused by things that are not in their extensions (Fodor, 1990c). Suppose, for example, that Mick's talking about his childhood pet dog reminds Scott of his childhood pet cat. In this case no misrepresentation is involved but the crude causal theory again entails inappropriate disjunctive contents. Now it entails that Scott's CATs has a content along the lines of cats or talk of pet dogs. This last aspect of the disjunction problem might be called the problem of representation in absentia: how do we explain our capacity to think about absent things? How do mental representations retain or obtain their contents outside of perceptual contexts? 

Asking how to alter the crude causal theory to allow for error is one place to begin looking for a more adequate proposal. One approach would be to try to describe certain situations in which only the right causes can produce the representation in question and to maintain that the content of the representation is whatever can cause the representation in such situations. This is sometimes referred to as a “type 1 theory.” A type 1 theory distinguishes between two types of situations, ones in which only the right causes can cause a representation and ones in which other things can too. A type-1 theory says that the first type of situation is content-determining. A type 1 teleological theory might state, for example, that the content of a perceptual representation is whatever can cause it when the perceptual system is performing its proper function, or when conditions are optimal for the proper performance of its function. The content of representations in abstract thought might then, it might be proposed, be derived from their role in perception. Not all teleological theories of content are type 1 theories, however. The theory described in the next section is arguably a variant of a type 1 theory but some of the theories described in later sections are not.
And here is a specific account of Papineau's teleosemantic model - this also comes from the Stanford Encyclopedia of Philosophy:
A further way in which teleological theories of content can differ is with respect to the contents that they aim to explain. David Papineau's theory, developed at the same time as Millikan's, will help illustrate this point. Papineau (1984, 1987, 1990 and 1993) develops a theory that is top-down, or non-combinatorial, insofar as the representational states to which his theory most directly applies are whole propositional attitudes (e.g., beliefs and desires). In early writings, Millikan sometimes seems to hold a similar view and some objections initially raised against her theory are based on this interpretation of her view (see, e.g., Fodor 1990b, 64–69, where he raises some of the following points).

In Papineau's theory, the contents of desires are primary and those of beliefs are secondary in terms of their derivation. According to Papineau, a desire's “real satisfaction condition” is “… that effect which it is the desire's biological purpose to produce” (1993, 58–59), by which he means that “[s]ome past selection mechanism has favored that desire — or, more precisely, the ability to form that type of desire — in virtue of that desire producing that effect” (1993, 59). So desires have the function of causing us, in collaboration with our beliefs, to bring about certain conditions, conditions that enhanced the fitness of people in the past who had these desires. Desires, in general, were selected for causing us to bring about conditions that contributed to our fitness, and particular desires were selected for causing us to bring about particular conditions. These conditions are referred to as their satisfaction conditions and they are the contents of desires.

The “real truth condition” of a belief, Papineau tells us, is the condition that must obtain if the desire with which it collaborates in producing an action is to be satisfied by the condition brought about by that action. A desire that has the function of bringing it about that we have food has the content that we have food, since it was selected for bringing it about that we have food, and if this desire collaborates with a belief to cause us to go to the fridge, the content of the belief is that there is food in the fridge if our desire for food would only be satisfied by our doing so if it is true that there is food in the fridge (Papineau's example).

This seems to reject the Language of Thought hypothesis, according to which thought employs a combinatorial semantics. Language is combinatorial to the extent that the meaning of a sentence is a function of the meanings of the words in the sentence and their syntactic relations. “Rover attacked Fluff” has a combinatorial meaning if its meaning is a function of the meaning of “Rover”, the meaning of “attacked” and the meaning of “Fluff”, along with their syntactic relations (so that “Rover attacked Fluff” differs in meaning from “Fluff attacked Rover”). According to some philosophers (see esp. Fodor 1975) the content of propositional attitudes is combinatorial in an analogous sense. That is, for instance, the content of a belief is a function of the contents of the component concepts employed in the proposition believed, along with their syntactic relations. A teleological theory of content can be combinatorial, for it can maintain that the content of a representation that expresses a proposition is determined by the separate histories of the representations for the conceptual constituents of the proposition (and, perhaps, by the selection history of the syntactic rules that apply to their syntactic relations). Papineau's theory is not combinatorial, at least for some propositional attitudes. Instead, the proposal is that the contents of concepts are a function of their role in the beliefs and desires in which they participate.

Papineau's theory is a benefit-based theory, and some issues discussed in the previous sub-section are relevant to an assessment of it. For instance, it is unclear that what we desire is always what is beneficial to fitness. One might want sex, not babies or bonding, and yet it might be the babies and the bonding that are crucial for fitness. However, this section will not attempt an overview of the strengths and weaknesses of this theory but will focus on issues peculiar to non-combinatorial accounts.

Any non-combinatorial theory must face certain general objections to non-combinatorial theories, such as the objection that it cannot account for the productivity and systematicity of thought (Fodor 1981, 1987). This entry will not rehearse that argument (see the entry on the language of thought hypothesis) but special problems for a teleological version of a non-combinatorial theory need to be mentioned. Consider, for example, the desire to dance around a magnolia tree when the stars are bright, while wearing two carrots for horns and two half cabbages for breasts. Probably no-one has wanted to do this. But now suppose that someone does develop this desire (to prove Papineau wrong, say) so that it is desired for the first time. We cannot characterize the situation in this way, according to a non-combinatorial teleological theory. Since it has never been desired before, it has no history of selection and so no content on its first occurrence, on that style of theory. It is also a problem for this kind of theory that some desires do not or cannot contribute to their own satisfaction (e.g., the desire for rain tomorrow or the desire to be immortal) and that some desires that do contribute to their own satisfaction will not be selected for doing so (e.g., the desire to smoke or to kill one's children). In contrast, teleological theories that are combinatorial have no special problem with novel desires, desires that cannot contribute to bringing about their own satisfaction conditions or desires that have satisfaction conditions that do not enhance fitness, as long as their constitutive concepts have appropriate selection histories or are somehow built up from simpler concepts that have appropriate selection histories.

Papineau can respond by agreeing that some concessions to a combinatorial semantics have to be made. Once some desires and beliefs have content, the concepts involved acquire content from their role in these and they can be used to produce further novel, or self-destructive or causally impotent desires. However, it needs to be shown that such a concession is not ad hoc. The problem is to justify the claim that the desire to blow up a plane with a shoe explosive is combinatorial, whereas the belief that there is food in the fridge is not.
Here is a selection of his papers available online through his personal website.

"Choking and the Yips" Phenomenology and the Cognitive Sciences forthcoming
"Sensory Experience and Representational Properties" Procedings of the Aristotelian Society forthcoming
"A Priori Philosophical Intuitions: Analytic or Synthetic?" in E Fischer and J Collins eds Philosophical Insights forthcoming
"Recanati On Mental Files" Disputatio forthcoming
"Can We Really See a Million Colours?" in P Coates (ed) Phenomenal Qualities forthcoming


What Is Wrong With Strong Necessities?” (with Philip Goff) Philosophical Studies 2013
"In The Zone" in A O'Hear (ed) Philosophy of Sport 2013
"The Poverty of Conceptual Analysis" in M Haug (ed) Philosophical Methodology 2013 (this is a revised version of "The Poverty of Analysis" 2009)
"Causation is Macroscopic but not Irreducible" in S Gibb and E Lowe (eds) The Ontology of Mental Causation 2013
"There Are No Norms of Belief" in T Chan (ed) The Aim of Belief 2013
"Phenomenal Concepts and the Private Language Argument" American Philosophical Quarterly 2011
"Realism, Ramsey Sentences and the Pessimistic Meta-Induction" Studies in History and Philosophy of Science  2011
"The Philosophical Insignificance of A Priori Knowledge" in M Shaffer and M Veber (eds) New Essays on the A Priori 2011
"What Exactly is the Explanatory Gap?" Philosophia 2010
"A Fair Deal for Everettians" in J Barrett, A Kent, S Saunders, and D Wallace (eds) Many Worlds? 2010
"Can any Sciences be Special?" in C Macdonald and G Macdonald (eds) Emergence in Mind 2010
Shorter Pieces Online

"Interview" in 3:AM Magazine 2013
"Can We be Harmed After We are Dead?" Journal of the Evaluation of Clinical Practice 2013
"What is X-Phi Good For?" The Philosophers' Magazine April 2010
Five Philosophy of Science Answers” R. Rosenberger (ed) Philosophy of Science: Five Questions 2010
"Top Universities: Only the Rich Need Apply" The Times 13 August 2009
The Causal Closure of the Physical and Naturalism” B. McLaughlin, A. Beckermann and S. Walter (eds) Oxford Handbook of the Philosophy of Mind 2009
Reply to Lewis: Metaphysics versus Epistemology” (withVictor Durà-Vilà) Analysis 2009
"Explanatory Gaps and Dualist Intuitions" in L. Weiskrantz and M. Davies (eds) Frontiers of Consciousness 2008
 “Five Philosophy of Social Science Answers” in D. Rios and C. Schmidt-Petri (eds) Philosophy of the Social Sciences: Five Questions 2008
A Thirder and an Everettian: Reply to Lewis’s ‘Quantum Sleeping Beauty" (with Victor Durà-Vilà) Analysis 2008
NaturalismThe Stanford Encyclopedia of Philosophy 2007
Three Scenes and a Moral: My Philosophical DevelopmentThe Philosopher’s Magazine 2007
"Review article of Gary Marcus's The Birth of the Mind" (with Matteo Mameli)  Biology and Philosophy 2006
The Tyranny of Common SenseThe Philosopher’s Magazine 2006
Naturalist Theories of Meaning” E. Lepore and B. Smith (eds) Oxford Handbook of the Philosophy of Language 2006
"Reply to Robert Kirk's and Andrew Melnyk's comments on my Thinking about Consciousness" SWIF Online Philosophy Forum 2003
Wow, that is a LOT of information.


Mind the brain

Sunday 8 June 2014

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Consciousness in a material world: Putting the mind back into the brain (Don Farrall/Getty Images)

Neuroscience might have banished dualist notions of mind and body but it seems that M. Descartes’ 350 year-old hunch will not go away. What hasn’t helped is the log-jam of schemes trying to explain the dreaded ‘c’ word. The race is on to build a brain, but the deeper neuroscientists dig into the soggy grey matter the more elusive consciousness becomes. It needn’t be according to leading philosopher of mind David Papineau. If only we could accept some deceptively simple advice.
Daivd Papineau - Professor of Philosophy of Science, King's College London

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