Žižek, on Malabou, on the brain sciences

Any Hegel scholars around? Žižek (2006, pp. 208–209):

“Where, then,do we find traces of Hegelian themes in the new brain sciences? The three approaches to human intelligence—digital, computer-modeled; the neurobiological study of brain; the evolutionary approach—seem to form a kind of Hegelian triad: in the model of the human mind as a computing (data-processing) machine we get a purely formal symbolic machine; the biological brain studies proper focus on the “piece of meat,” the immediate material support of human intelligence, the organ in which “thought resides”; finally, the evolutionary approach analyzes the rise of human intelligence as part of a complex socio-biological process of interaction between humans and their environment within a shared life-world. Surprisingly, the most “reductionist” approach, that of the brain sciences, is the most dialectical, emphasizing the infinite plasticity of the brain.”

This is the beginning of an interesting (or at least confusing) section on relationships between society, brain, mind, free-will, and so on, and so forth. A reading group would be tremendously helpful. (Page 13 discusses fisting, if that acts as a motivator. Yes, I have just been scanning through for the important topics.)

Reference

Slavoj Žižek (2006). The Parallax View. The MIT Press.

The meaning of meaning?

(Made with SpringNet.)

A non-judgmental reconstruction of drunken logic

Simmons (2007) makes a helpful contribution to the logical modelling of real arguments by an addition of the shot glass modality to intuitionist logic.  A snippet:

Per Per Martin-Löf [7], something is true when witnessed by an object of knowledge, which lends itself to an obvious question of whether the truth of a proposition can be obviated by the presence of alcohol, seeing as alcohol has an clearly negative impact on one’s knowledge [1]. The possibility of the analytical truth of a proposition becoming questionable under the influence is also evidenced by discussion as to whether conference submissions that can be understood while drunk are novel enough to be worth accepting.

I think the following inference rule which I discovered while living in the homeland of Martin-Löf still requires further investigation:

Reference

Robert J. Simmons.  A non-judgmental reconstruction of drunken logic.  Presented at SIGBOVIK 2007, April 1, 2007. Winner of the Best Paper raffle. [PDF]

A reasoning task

Any mathematical physicists out there? Can the “EASILY TESTABLE FORMULA” published by Tipler (2008) really be easily tested? Would the result say anything about the Many Worlds Interpretation?

Frank J. Tipler (2008). Testing Many-Worlds Quantum Theory By Measuring Pattern Convergence Rates, arXiv:0809.4422v1.

Death and furniture

Found this paper by Edwards, Ashmore, and Potter (1995) amusing as recently I tapped a table to make a point about different levels of analysis. From the intro:

When relativists talk about the social construction of reality, truth, cognition, scientific knowledge, technical capacity, social structure, and so on, their realist opponents sooner or later start hitting the furniture, invoking the Holocaust, talking about rocks, guns, killings, human misery, tables and chairs. The force of these objections is to introduce a bottom line, a bedrock of reality that places limits on what may be treated as epistemologically constructed or deconstructible. There are two related kinds of moves: Furniture (tables, rocks, stones, etc. — the reality that cannot be denied), and Death (misery, genocide, poverty, power — the reality that should not be denied). Our aim is to show how these “but surely not this” gestures and arguments work, how they trade off each other, and how unconvincing they are, on examination, as refutations of relativism.

And the point about levels is made:

It is surprisingly easy and even reasonable to question the table’s given reality. It does not take long, in looking closer, at wood grain and molecule, before you are no longer looking at a “table”. Indeed, physicists might wish to point out that, at a certain level of analysis, there is nothing at all “solid” there, down at the (most basic?) levels of particles, strings and the contested organization of sub-atomic space. Its solidity is then, ineluctably, a perceptual category, a matter of what tables seem to be like to us, in the scale of human perception and bodily action. Reality takes on an intrinsically human dimension, and the most that can be claimed for it is an “experiential realism”

Reference

Edwards, D., Ashmore, M. and Potter, J., (1995). Death and furniture: The rhetoric, politics and theology of bottom line arguments against relativism, History of the Human Sciences, 8, 25-49.

Psychological Therapies NOS Development Project

(Follow up to this post.)

• Link to background and documents
• An article by Andrew Billen in the Times
• Three replies. I particularly like what Malcolm Allen, Chief Executive Officer, British Psychoanalytic Council, has to say: “Psychoanalytic psychotherapy is taking its place as an effective, evidence-based intervention within contemporary mental health provision. We are not helped by those who try to make psychoanalysis into a mystery cult.” (Emphasis mine.)

Some quick thoughts on individual differences

Tom asked if I had any papers on the dangers of ignoring individual differences. Here goes with a bit of a brain dump.

I view individual differences as trying to pull out a little bit more from the residual term. Contrast these approaches:

1. If I do A to a load of people then on average B happens (but with a bit of noise).
2. If I do A to a load of people, then those who have property P do B, those with property Q do C (and there’s a bit of noise, but less than in setup 1). (Hence the derogatory response to individual differences research: “Oh you’re just modelling the noise term”.)

Much individual differences research is a bit dull, so I’m not surprised it is criticised: collect a load of data, preferably Gaussian distributed and obtained by summing many items, and examine the correlation structure (sometimes disguised with a spot of structural equation modelling).

Here’s a little example I happen to like. Some people interpret some A are B as meaning some and possibly all; others interpret it as some and not all. Two things you can do: try to force people towards one or other interpretation; or take an individual differences approach, find some other way to guess whether people are good at language pragmatics, and see if that predicts their interpretation of some A are B. I think both are important. The former is about trying to increase the probability that more people will understand what you mean (so you could imagine—and presumably psycholinguists do this—showing people big wads of text and seeing what influences ambiguity of interpretation). The individual differences approach is interesting as much of the information we deal with in life is ambiguous, and people seem to differ in how they deal with language and social context, how often they ask questions, etc, so it’s nice to leave things a bit ambiguous, one might even go as far as to say more ecologically valid, and characterise how people deal with it.

(Well actually there’s at least one other thing you can do: focus on areas of psychology where there are negligible individual differences: brick-to-skull manipulation and so on.)

Ignoring individual differences can be a bit dangerous. Suppose you want to model processes based on empirical data. If you assume everyone is doing the same thing, and just average across responses, then your model is not going to be very good. And forcing people to do the same thing can be a bit authoritarian.

I hate methodological papers. I like methodological asides in ordinary papers. Here’s one (from the abstract of Guasti et al 2005):

“… some of the manipulations of the experimental context have an effect on all subjects, whereas others produce effects on just a subset of children. Individual differences of this kind may have been concealed in previous research because performance by individual subjects was not reported.”

Or from Stenning and van Lambalgen (2005, p. 924):

“… although a considerable number of Byrne’s subjects (about 35%) withdraw the modus ponens inference after the second conditional premiss is presented, many more (about 65%) continue to draw the inference. What interpretation of the materials do these subjects have? If it is the same, then why do they not withdraw the inference too? And if it is different, then how can it be accommodated within the semantic framework that underpins the theory of reasoning? Does failure to suppress mean that these subjects have mental logics with inference rules (as Byrne would presumably would have interpreted the data if no subject had suppressed)? The psychological data is full of variation, but the psychological conclusions have been rather monolithic.”

I quite like this too, on the subject of longitudinal analyses but much more general (Bauer et al 2002, p. 202):

“The logic of deductive longitudinal analyses represents a clear advance over the assumption that all children follow a universal language trajectory. A priori hypotheses about group differences are evaluated with reference to individual developmental trajectories. However, individual variation that is not explained by group differences is relegated to a residual or error term. Given the crudeness of many of the hypotheses in the social sciences, it is often the case that much of the observed variation in individual trajectories is allocated to the residual term. The deductive approach thus seems to be at odds with an explicit focus on individual differences, in that departures from normative patterns are regarded as random error and typically are not investigated.

“The alternative, “inductive” approach seeks to maximize the information that can be gained from the individual trajectories themselves. In contrast to theory driven deductive methods, which evaluate differences between predefined groups, inductive methods are data driven and are used to examine the natural structure of individual differences. These methods are sometimes referred to as pattern oriented, person centered, or personalogic because they begin by examining similarities and differences in individual developmental patterns (see Cairns, Bergman, & Kagan, 1998, for a review). Using this bottom-up strategy, decision rules or clustering procedures are used to aggregate individuals into groups that display similar developmental patterns, irrespective of their status on theoretically relevant predictor variables.“

References

Bauer, D. J.; Goldfield, B. A. & Reznick, J. S. Alternative approaches to analyzing individual differences in the rate of early vocabulary development. Applied Psycholinguistics, 2002, 23, 313-335

Guasti, M. T.; Chierchia, G.; Crain, S.; Foppolo, F.; Gualmini, A. & Meroni, L. Why children and adults sometimes (but not always) compute implicatures. Language and Cognitive Processes, 2005, 20, 667-696

Stenning, K. & van Lambalgen, M. Semantic Interpretation as Computation in Nonmonotonic Logic: The Real Meaning of the Suppression Task. Cognitive Science, 2005, 29, 919-96

Mental Representation

Over at the Stanford Encyclopedia of Philosophy an update has recently been posted of the entry on mental representation by David Pitt.

When reading these kinds of articles, I look for a couple of things: (a) discussion of the importance of different levels of description and that they may be mapped onto each other; (b) clear language separating personal and sub-personal level descriptions.

It’s not bad. He notes for instance Smolensky’s arguments that “certain types of higher-level patterns of activity in a neural network may be roughly identified with the representational states of commonsense psychology”. BUT two issues to be separated here: classical notions of representation and how these relate to connectionist representations—and models even closer biologically; and also how phenomenology could arise from, e.g., connectionist networks.

Worth a read.

The Tractable Cognition Thesis

Spotted a nice paper from Iris van Rooij (2008) today, a study of ideas of how computational tractability can influence the choice of computational-level theories of cognition. She notes that many cognitive scientists assume that a theory is tractable if it is computable in polynomial time (the P-cognition thesis). Instead she argues for fixed-parameter tractable (FPT-cognition).

The general problem faced by researchers is what to do if one discovers that one’s computational-level theory is, e.g., NP-hard. The author categorises four alternatives:

1. Reject the framework, choose something else.
2. Revise the theory.
3. Devise heuristics.

So for instance she cites Oaksford and Chater’s rejection of logicist cognitive science and embrace of Bayesian networks—which are again intractable in general.

It sounds commonsenical—and many P-cognition algorithms can be horrendous in theory and practice, as van Rooij points out! It’s great to have this all spelled out in detail, with the maths, examples, and a careful analysis of the literature.

Here are the author’s recommendations.

1. Make explicit assumptions about (bounds on) the range of values that relevant input parameters can take in reality.
2. Analyze the parameterized complexity of the theory for all relevant input parameters that can reasonably be assumed to be much smaller than the whole input size.
3. Derive predictions from function restrictions to tractable parameter ranges and put them to an empirical test.
4. If no tractable parameter ranges can be found, or none that passes empirical tests, then revise the theory and return to Step 1.

Reference

Iris van Rooij (2008). The Tractable Cognition Thesis Cognitive Science: A Multidisciplinary Journal, 32 (6), 939-984 DOI: 10.1080/03640210801897856

General and useless

Wise words(?) from The Last Psychiatrist:

Please do not say the words “dopamine” and “nucleus accumbens” anywhere near me, I still have my old sack of doorknobs.  These explanations could not be more general and useless.  Using those two in support of a common addiction pathway is like involving “gasoline” and “spoons” in the diathesis for serial rapes.  Even though these are involved in various “addictions”—cocaine, alcohol, internet, sex—these “addictions” and their associated behaviors are so disparate that the pathway serves no useful clinical target.  Haldol blocks dopamine in the nucleus accumbens, but you can’t cure alcoholism with it, can you?

I’m not denying that such a pathway exists, I’m doubting the utility of this information, even if true.  Call me when science catches up to your lies.