Wednesday, December 21, 2011

Introduction to the next few posts.

Over the next few months almost all of my intellectual effort is going to be focused on the writing of my dissertation.

This is the first time that I have ever "done genuine science", that is, the first time that I have designed and run an experiment and so I thought it might be interesting to post regular updates about the various stages of composing the final text that documents the empirical and analytical work I've done and any of my findings (or failures to find).

My background is in philosophy, and so moving to a more empirical mode of thinking has been a difficult transition. It's quite different, indeed, the most unexpectedly different and difficult part of doing empirical work has been realising just how much work - sweat and greasy elbows work - is required to actually design and run an experiment.

Some of the topics I want to deal with in the next 6 months are:
  • Mental Rotation (what it is, neurobiologicial evidence for it, training it)
  • Tetris (Expertise, training, any cognitive benefits)
  • Situated/Embodied/Embedded Cognition
  • Statistics (R, techniques, nightmares etc.)
  • The software/typesetting system I'm using to compose the document (LyX and LaTeX)
By this time next week I will have posted my first piece on Mental Rotation - specifically, covering just what it is and describing Shepard and Metzler's seminal 1971 paper. I'm hoping at least some of this will make it into the final dissertation.

Tuesday, December 6, 2011

First stab at Maze Generation

This is a quick and dirty first stab at Maze generation using recursive backtracking and the HTML5 Canvas element. It's the first in what I hope will be a series of experiments with Canvas.

Sunday, October 2, 2011

UKZN/Meraka KRR MAIS '11

So last week I spent a week among computer scientists at the UKZN/Meraka KRR Masters Artificial Intelligence Spring School 2011.

I was initially a bit apprehensive, I was almost certainly going to be the only non-computer scientist among them. Although I'm in cognitive science/philosophy (both of which have quite strong ties to computer science on their best days) I was concerned that my lack of a more advanced background in theoretical computer science and logic would be a hindrance and that I would be stuck staring blankly at pages of formulae that made as much sense to me as ancient Sanskrit.
Thankfully, that wasn't the case.

The primary coursework for the week was Allesandro Artale's "Formal Methods" - which was firmly based in Formal Logic - more specifically, the course deals with "model checking" - which is the process of checking whether some or other property holds over a model of some system. The system in question could really be anything that's able to be modelled formally, but the focus was on modelling software systems.
The course is meant to be - I think - run over a number of weeks, so the pace was quite brisk and I could have used a little more time to digest some of the concepts - but I learned a hell of a lot. The highlight of the course, for me, was the discussions of the syntax and semantics of a number of temporal logics, which I have only barely touched on before. Temporal logic is really just a species of modal logic, so if you've done the latter the former will be easily digestible. Specifically, we looked at Linear Temporal Logic (LTL), Computational Tree Logic (CTL), and CTL* (which is a superset of LTL and CTL). Once we had a decent grasp on the semantics of these Logics we moved on to verifying whether particular kinds of properties help over models described in these languages.
We also did a little practical on specifying models and checking properties using the application NuSMV ... I'd like to see how this is used in industry (if it is) because we really only looked at toy examples.

The Formal Methods course ran across the whole week, from 9-12 every morning. In the afternoons there were tutorials (one on Hyper-heuristics, and another on "SAT and efficient boolean reasoning" that I had to miss because of work). Other than that there were presentations of various hons, Msc, and PhD projects being done at UKZN and Meraka's KRR group.

Oh, and if anyone from the Spring School reads this, thank you so much for letting me sit in - I'll most certainly be back next year.

Monday, September 12, 2011

The "end of philosophy"

I've just read a gloriously stupid discussion online where a number of science "fans"* were having a discussion about the status of "philosophy".

Except for one of the contestants, both the pro-philosophy and against-philosophy people had cringe-worthy arguments. The primary instigator seems to hold some kind of quasi-instrumentalist-positivist mishmash of a position, whereas some of the defenders seem to think that philosophy is nothing more than a bunch of techniques with which one can use to straighten up your thinking.

Perhaps the debate had something to do with Stephen Hawkings saying something about philosophy being dead? Maybe, maybe not ... but ...
What I think is most interesting about all of this this is that these people think that what they're saying would somehow be news to philosophers. In a discipline whose business is more or less to approach everything (everything ever) from a critical perspective you would think that at least someone would have thought "hey, what about philosophy? What is its status as a discipline?".

Of course they have. Duh.

In fact, to quote one of the books I read for an undergraduate course (entitled, if you can believe it, "After philosophy: end or transformation" by Baynes, Bohman, and McCarthy)

Agonizing over the "wherefore" and "whither", and even the "whether" of philosophy has been a staple of Western philosophical discourse since the time of Socrates and Plato. One might even argue, and with good reason, that periods in which self-doubt ran deepest were often periods of extraordinary philosophical creativity.

Following Baynes et al. one could take the "agonizing" of African philosophers around the mid to late 20th century about the status and possibility of a uniquely "African philosophy" to have been the very foundation that constituted a uniquely African tradition of philosophy.

Furthermore, the philosophers I know happen to be huge science fan boys and girls themselves, primarily because most philosophers are deeply committed to truth in some way or another - and science happens to be one of the most productive human activities in the way of truth production - what is there for philosophers not to like?

Well, perhaps there are some things. "Science", being a human endeavour, can on occasion set off down on paths that lead nowhere, and this is where philosophy comes in pretty handy sometimes.

Let's take an example that I'm interested in - namely, Artificial Intelligence (I'm sure there are examples in other disciplines, I'm just most familiar with this one). Back in the 1960's AI research was really kicking into high gear - researchers were convinced that within a few years they would have computer programs demonstrating human level intelligence in a variety of domains.

Then Hubert Dreyfus came along and spoiled all of the fun. Dreyfus, by the way, is a navel gazer who specialises in certain continental (gasp, horror) philosophers (Heidegger, Kierkegaard, Foucault, among others).
Anyway, Dreyfus noticed that the AI researchers were working with certain unstated philosophical assumptions that reached back to at least Descartes and which had been put to rest - as far as Dreyfus was concerned, anyway - by some of the people who he had studied.

I'm not quite sure how many people paid much attention to Dreyfus' critique - I know at least one very prominent AI researcher changed direction after taking in what Dreyfus had to say. Nonetheless, time has been kind to Dreyfus and not so kind to what has come to be known as "good old fashioned AI".

The point is, though, that scientists can learn from philosophers - at least some of the time. Philosophers certainly learn from science (even if there is a minority who may have anti-science tendencies). This is because, as I said above, both of the disciplines are pretty much dedicated to the truth - whatever that ends up meaning, and whatever means we use to get to that end.

* I'm not quite sure what else I can call this kind of person - but the SMBC pic I posted should help you recognise 'em when you see 'em

Thursday, June 23, 2011

1st semester in review

So my first semester as a cognitive science grad student at UKZN is done and dusted.

Here are the high points :

* my seminar on Dennett's book Freedom Evolves with Prof. David Spurrett.
* Writing a nice long - somewhat critical - paper on Experimental Philosophy.
* Writing a research proposal on Tetris and Mental Rotation.
* Having said proposal accepted - research can now commence.

So what's next? Well, in the second semester I'll be

* Carrying out the experiments described in my proposal
* Writing at least first drafts of my lit review and methodology sections of my dissertation.
* Doing some research on behavioural economics
* Generally hanging around the department a bit more (I might have an office next semester - cool)

I'm still not sure if I'll get much time to blog next semester (I still work full time, you know) but I'll try post about the stuff I'm working on.

Thursday, May 5, 2011

Should we be surprised? X-phi meta-survey results

There's a post up on the Experimental Philosophy Blog detailing an in-progress study by Billy Dunaway and his collaborators - it's a meta-survey that tries to assess whether philosophers can accurately predict the results of other X-phi surveys.

It turns out that philosophers don't do too badly when guessing which way the "laity" would go :
"at least 73% of philosophers who claimed to have no prior familiarity with these studies predicted how non-philosophers would respond"

I don't think that we should be surprised by this result though - we wouldn't be surprised if philosophers were given a survey to guess what kinds of inferences non-philosophers would make when presented with arguments containing informal fallacies. I'm not suggesting that critical thinking and the deployment of intuitions are perfectly analogous, but rather that at least part of what philosophy does is modify one's intuitions the same way in which critical thinking modifies one's deployment of reason (in fact, I think that there is at least some reason to think that the two are related - this is for another time though).

The study does a couple of interesting things - Firstly, it shows that philosophers aren't entirely out of touch with folk intuitions. David Manley raises an interesting question here though when he asks "are theorists who specialize in a particular area more likely to be out of touch about folk intuitions in that area?"
Secondly, it shows that philosophers have at least some notion that intuitions can vary along dimensions that are not philosophically relevant (in this case, with the amount of training a person has). Whether this shows that philosophers are in any sense experts at intuitions is questionable, but it does show that there is at least some critical self-awareness (and, really, we do philosophers a disservice to think that they would be anything by critically self-aware, however ensconced in the "armchair" they might be)

It's going to be interesting to watch the discussions around this work in the next few days. If something cool comes from it, I'll post it up here.

Thursday, April 28, 2011

Fear of Knowledge

As I mentioned in an earlier post, I was going to be reading Paul Boghossian's Fear of knowledge : against Relativism and Constructivism for a course I was auditing.

Boghossian's strategy is to set up the strongest versions of the claims that are supposed to support relativism. He then goes about showing why - even given their best shot - they fall short of their mark. I wont spend time rehashing his arguments, his book is short and the arguments are clear and tight, any further compression seems unnecessary - if this is the kind of thing you're interested in, then the book itself is what you want to peruse.

It's possible that philosophy mavens might take issue with parts of Boghossian's book. There are certainly some technicalities to these debates that might complicate matters - as Boghossian himself notes in annotations scattered throughout the text.
This isn't really a problem for Boghossian though - the intended audience is not necessarily philosophers, but rather educated people in general. Specifically, people who find themselves drawn to relativism or constructivism for some or other reason. These are not people who have been convinced of relativism as a consequence of years of deep immersion in epistemology, but who have, perhaps, picked up the "profound" relativistic insight from a book on cultural theory, or a course in post-colonialism. It is primarily for this kind of reader that Boghossian wrote his little book.
That having been said, there is much in here for long time students of philosophy, especially for those like myself who have grown up on the "fuzzy" side of the divide.

I'm happy to say that I can recommend the book without reservation - if you find yourself attracted to, or even endorsing, some vague form of relativism, read this book and then reconsider.

Wednesday, April 20, 2011

Does defending intuitions against restrictionism require more Experimental work?

There is a common response to the restrictionist challenge (see my last post for a sketchy overview) called the "expertise defence" that makes the claim (which we'll accept for the sake of argument) that :

Φ - on the grounds of their philosophical training, some people are expert philosophical intuiters.

What are the consequences of Φ? The first thing it manages to do is to undermine the results of the existing studies that claim to derive some kind of philosophical raw data from the intuitions of the folk because the folk are just the wrong people to ask about these things. As such, Φ helps meet the current version/state of the restrictionist challenge. However, establishing Φ doesn't necessarily help fend off restrictionism, in fact, it opens up the possibility of a stronger challenge.

To see how this might be, consider the possibility that two philosophers have conflicting intuitions about some thought experiment / application of a concept / whatever. Note that nothing about Φ rules these kinds of conflicts, all Φ serves to establish is that philosophers' intuitions should be considered as the "proper" source of intuitions about philosophical matters.
There are a number of possible responses to this situation.

Our first would be to reject these conflicting intuitions straight out - doing this is actually just to reassert the restrictionist's challenge, only focused on a narrower domain.

Our second response could be to assert an updated version of the expertise defence, let's call this

Φ* - on the grounds of specific kinds of philosophical training, a subset of philosophers are expert intuiters.

Even if we grant Φ* though we have a problem - this is actually identifying which kinds of training lead to expert intuitions. The answer to this question will be at least partly empirical - we can't hope to come to any useful conclusions about the nature of the training required to support Φ* without actually going out into the field (I've also ignored the fact that in order to even establish a claim as strong as Φ* we would need some kind of empirical evidence to back it up).

Does defending intuitions against restrictionism require more Experimental work?
Any thoughts?

For more on this check out Weiberg et al's Are philosophers expert intuiters?

Monday, April 18, 2011

Experimental philosophy - themes and methods

I thought I'd post something on experimental philosophy, intuitions and philosophy because I may be writing some stuff about it in the coming weeks - so what follows tries to lay out some of the basics. If you're interested in experimental philosophy (either for or against) I suggest you check out the Experimental philosophy page - from there you can get access to draft versions of most of the important work being done in the field (again, for or against ...)

So ... How are we to understand appeals to intuitions in philosophy? Whose intuitions are being appealed to when philosophers state that some claim or position is intuitive?

Proponents of “Experimental Philosophy”, a burgeoning movement in (mainly) English speaking philosophy, interpret at least some of these claims about intuitions to be hypotheses about the pre-theoretic judgements of non-philosophers. Further, philosophers who identify with Experimental Philosophy, or X-phi, typically hold that assessing claims about “what is intuitively plausible” or whether “we intuitively judge X to be a Y” is best done not simply through traditional armchair reflection but by going out into the world and conducting systematic experimental studies to determine just what and how the “folk” think (Knobe, 2007 : 96). Here we will provide an overview of some of the important trends in X-phi and the nature of the challenges that they raise for appeals to intuition in philosophy.

Experimental Philosophy is not a deeply unified research project, a fact that is sometimes missed by its critics (Nadelhoffer & Nahmias, 2007 : 124). It is rather a loose collection of different projects with diverse aims and approaches that find what unification they have through their broad acceptance of the claim that empirical data are important for philosophical work. Further, and importantly, philosophers and psychologists who identify their work with X-phi are actively involved in running experiments and analysing the resulting data themselves. This latter point about experimental engagement serves to distinguish Experimental Philosophy from other kinds of philosophy that may be deeply informed by the natural and social sciences (Nadelhoffer & Nahmias, 2007 : 124). Although work in X-phi is rather diverse in it's ends as well as in its objects of study – there has been experimental work carried out on, among other things, ethics, causation, and free-will – there has been a fairly constant methodological thread running through most of the past and current work. This is the heavy use of surveys and polling (Cullen, 2009 : 1-4). There is no principled commitment to any particular methodology though, any and all experimental techniques are available for use by Experimental Philosophers. For Example, Joshua Greene's celebrated work in moral psychology and meta-ethics (Greene, 2002) makes heavy use of neural imaging data from his fMRI studies and Tamler Sommers has recently (2010 : 210) suggested that Experimental Philosophers could get philosophical mileage from designing behavioural experiments that might shed light on, inter alia, how subjects' explicit moral judgements might correspond, or fail to correspond, with behavioural responses.

The empirical work on the cluster of questions surrounding free will, determinism, and moral responsibility has been conducted almost exclusively through surveys ( for examples see Nahmias, Morris, Nadelhoffer, & Turner, 2004, 2006; Knobe & Nichols 2007; Feltz & Cokely, 2008; ). We now turn our attention to this work.

Experimental Analysis

The seminal studies of Nahmias, Morris, Nadelhoffer, and Turner (NMNT) provide a useful entry point into the field (Nahmias, Morris, Nadelhoffer, & Turner, 2004,2006).
In their work NMNT provide a number of examples where philosophers such as Robert Kane, Galen Stawson, and Thomas Pink have claimed that the folk are “natural incompatibilists”. By making the claim that their positions are in accord with common sense incompatibilists but the burden of proof on compatibilists to show both why our common-sense intuitions are wrong as well as why we would have misleading intuitions in the first place ( Nahmias, Morris, Nadelhoffer, & Turner, 2006 : 564). NMNT then argue that philosophers who make claims that their theories are somehow supported by, or are in accord with, our everyday intuitions are making claims that can and should be tested empirically.

In order to test these claims about people's natural compatibilism, NMNT ran a series of experiments that were designed to “directly probe” (Sommers 2010 : 201) the folk's intuitions on these matters. In one of these experiments participants were presented with a vignette which described a world in which a Laplacian version of Determinism holds. It the vignette they described a world in which scientists have built a supercomputer that is able to accurately predict events that will happen in the future. These scientists then use this computer to determine, twenty years before he is even born, that a man named Jeremy Hall will rob a particular bank at a particular time. As predicted, Jeremy Hall robbed the predicted bank at the predicted time. Subjects were then asked a series of questions meant to interrogate their intuitions about Jeremy's freedom and responsibility. When they were asked whether they thought that Jeremy acted of their own free will, 76% of the participants answered that he did. Further, when questioned directly about whether Jeremy was “morally blameworthy for robbing the bank”, 83% of the participants responded that he was indeed responsible (Nahmias, Morris, Nadelhoffer, & Turner, 2006 : 567-568).
NMNT interpret these responses as being in favour of compatibilism. While they are careful to stress that they do not think that their results are any bearing whether or not any particular account of free-will is true, NMNT argue that their results potentially undermine the claims of “naturally incompatibilism” and argue that the burden of proof for motivating their theories of free-will (at least in the case of the more “metaphysically demanding” libertarian accounts) should therefore fall on the shoulders of the incompatibilists.

NMNT's experimental work is an attempt to get at the actual content of the folk's intuitions and concepts. As such it falls into the broad category of Experimental Analysis, or what Kauppinen calls “positive experimentalism” (Kaupinnen, 2006). Experimental Analysis comprises of work intended to explore, through empirical methods, the contents of the folk's intuitions and concepts and then determine the relevance of the results for current and future work in philosophy (Nadelhoffer & Nahmias, 2007 : 126). The philosophical relevance of these data might be, as it is with NMNT's work, determining burden of proof through to providing the raw data for revisionist theories of free-will or ethics. Whatever the project, if it makes reference to common-sense concepts or intuitions, Experimental Analysts think that it is somewhat premature to come to philosophical conclusions without first determining the content of these concepts and intuitions empirically (Nadelhoffer & Nahmias, 2007 : 126).

Experimental Descriptivism

Experimental Descriptivists, while sharing an interest in determining the content of folk intuitions, are additionally interested in understanding the psychological mechanisms and processes through which these intuitions are generated ( Nadelhoffer & Nahimais, 2007: 127). Knowledge about these psychological mechanisms are then used in the service of philosophical argumentation to support, or attack, “first-order” philosophical theories (Nadelhoffer & Nahimais, 2007: 127). Consider recent work in the free-will debate by Knobe and Nichols (2007). They presented participants in their experiment with a scenario describing a universe (universe A) in which

“everything that happens is completely caused by whatever happened before it … so whatever happned at the beginning of the universe caused whatever happened next, and so on right up until the present. For example, one day John decided to have French fries for lunch. Like everything else, this decision was completely caused by what happened before it. So, if everything in this universe was exactly the same up until John made his decision, then it had to happen that John would decide to have French fries” (Knobe & Nichols, 2007).

All participants were assigned to one of two groups. The first group was asked whether, in universe A, “it is possible for a person to be morally responsible for their actions?” to which 86% of the group responded in the negative (Knobe & Nichols, 2007). The second group was presented with a further vignette describing a man in universe A who falls in love with his secretary and who kills his family by burning his house down while they were trapped inside in order to be with her. When members of this second group were asked to judge whether the man was morally responsible for his actions to which 72% of the group responded in the affirmative (Knobe and Nichols 2007). The experimental method used in this study follows that of the NMNT study described above, however, the aim was not just to test a hypothesis about the content of folk intuitions but rather to test a theory about the way in which those intuitions are generated. Knobe and Nichols hypothesised that compatibilist intuitions might be triggered by “affect-laden” scenarios and, indeed, this hypothesis seems to be borne out in their results – the scenario in which the man kills his family was designed to affect the participant's emotions which then drew an overwhelmingly compatibilist response. Knobe and Nichols then try and account for their results by advancing a theory in which compatibilist intuitions reflect a kind of “performance error” (Appiah, 2008 : 102) and therefore, contrary to NMNT's conclusions, shouldn't count in compatibilism's favour.

Experimental Restrictionism

One notable feature of the experiments already discussed is that the responses aren't unanimous. For the 72% of participants who gave compatiblist answers in Knobe and Nichols' “high affect” scenario there was a substantial dissenting minority of participants who didn't. While Knobe and Nichols' affective performance error theory might be able to account for the general trend towards compatibilism we still stand in need of an explanation of why we see such a high number of responses for incompatibilism. Explaining these kinds of results has opened up a line of research that attempts to uncover correlations between differences in individuals and their intuitions. For example, in a 2009 study Feltz and Cokely set out to investigate whether and how differences in peoples' personalities were related to their intuitions concerning determinism and attributions of moral responsibility. Before presenting participants with surveys similar to the experiments already discussed, participants were administered a brief version of the Big-Five personality test. The Big-Five model of personality identifies five broad traits (Extroversion, Neuroticism, Agreeableness, Conscientiousness, and Openness to experience) that appear as common factors across a range of different personality scales and that seem to be stable across different cultures (de Bruin, 2005 : 159). Feltz and Cokely found that measures of extroversion of personality were a reliable predictor of compatibilist responses to their survey questions (Feltz & Cokely, 2009). Among the possible interpretations that they suggest that their data support is the notion that there might not be a homogeneous set of folk intuitions at all, and further, that the long-standing debate about free-will that we see in professional philosophy could in part be due to differences in philosophers' personalities triggering different intuitions about free-will and moral responsibility (Feltz & Cokely, 2009 : 7).
Considerations along these lines, experimental results that show that intuitions my vary along socio-economic and cultural lines (Nadelhoffer & Nahmias, 2007 : 124) are sometimes thought to be reason enough to be suspicious of the use of intuitions in philosophical argumentation in general. This is the broad claim of the Experimental Restrictionists who are in some respects the most radical of the proponents of Experimental Philosophy. The central claim of Experimental Restrictionism is that empirical evidence showing the diversity and unreliability of intuitions should undermine philosophers' confidence in both appeals to the intuitions of the folk and to the more “discriminating” intuitions of philosophers.


Appiah, K. A. (2008). Experiments in Ethics. Harvard University Press : Cambridge, Massachusetts.

Cullen, S. (2009). "Survey-Driven Romanticism" Rev.Phil.Psych

de Bruin, G. P. (2005). "Personality Assessment" in An introduction to Psychological Assessment in the South African context Foxcroft, C. & Roodt, G. (eds) Oxford University Press Southern Africa : Cape Town.

Feltz, A. Cokely, E., T., (2009). "Do judgments about freedom and responsibility depend on who you are? Personality differences in intuitions about compatibilism and incompatibilism." Consciousness and Cognition 18: 324-350.

Greene, J. (2003). "From neural 'is' to moral 'ought' : what are the moral implications of neuroscientific moral psychology?' Nature Reviews : Neuroscience Vol. 4 : 847 – 850.

Kauppinen, A. (2007). "The Rise and Fall of Experimental Philosophy", Philosophical Explorations Vol. 10, No. 2: 95-118.

Knobe, J. (2007). "Experimental Philosophy and Philosophical Significance", Philosophical Explorations 10(2): 95-118.

Nadelhoffer, T., Kvaran, T., & Nahmias, E. (2009) "Temperament and intuition : A commentary on Feltz and Cokely" Consciousness and Cognition

Nahmias, E., Morris, E. G., Nadelhoffer, T. & Turner, J (2004). "The Phenomenology of Free Will" Journal of Consciousness Studies 11(7-8): 162-179.

Nahmias, E., Morris, E. G., Nadelhoffer, T. & Turner, J (2006). "Is Incompatibilism Intuitive?" Philosophy and Phenomenological Research Vol. LXXIII : 28-53.

Nadelhoffer, T., Nahmias, E. (2007). "The Past and Future of Experimental Philosophy" Philosophical Explorations. Vol. 10, No 2.

Sommers, T. (2010). "Experimental Philosophy and Free Will" Philosophy Compass. 5/2 : 199-212.

Tuesday, March 8, 2011

*edit* Infrequent posting

With my own research kicking into high gear now I doubt I'm going to have much time to update this blog, at least during 2011. I'll post when something particularly interesting comes along though.

Thanks for reading :)

Thursday, February 3, 2011

UKZN, epistemology and Logic

This coming Monday I'm starting coursework at UKZN and alongside my Cog.Sci seminar, my supervisor has invited me to attend some lectures on Epistemology

I think the course is based around Paul Boghossian's book Fear of Knowledge - and, to be honest, I'm really looking forward to this course. In the preface of his book Boghossian mentions that he spends, or might seem to spend, a fair amount of time beating up on the work of Richard Rorty.

Now Richard Rorty has been a fairly big influence on me, I was introduced to him way back when I did a third year course on "post-modern" epistemology and was, largely, taken in by his style. I'm sure anyone who has read much of Rorty will know what I mean.

I know that at the time I was also quite impressed with his views of knowledge, and his book Philosophy and the Mirror of nature knocked my naive ideas about the progress of ideas and truth flat on my ass (never mind the fact that my "naive" ideas have turned out to be closer to my older more considered views ...)

I was in awe of the man, and of his ideas, and I devoured everything of his that I could get my hands on (and understand).
But as I've progressed I've come to see some real problems with his positions, both political and epistemological - this article by Susan Haack is a good place to start getting the picture - and so rather than rejecting him outright, I find myself reading him these days in the same way that I read Emerson, as an essayist or even a poet, not as a philosopher trying to get at truth ... somehow I doubt Rorty would have had a problem with that though.

So I'm consciously going into this course with the intention of gathering up all the forces, marshalling all of the arguments, mustering all of the intellectual muscle I can against Rortyism and crushing my younger self.

It's going to be fun.

Related to this, I've been digging through my old notes on Epistemic Modal Logic and trying to supplement my reading online. I've found a couple of useful resources.
The wikipedia page on Epistemic Modal Logic is good for a quick orientation, but is thin on details. For a more comprehensive treatment a good place to go is the SEP's entry on Epistemic Logic and follow up on some of the references there.

Then I've found a really nice resource on "The science of computational logic" which is a course run as part of the EM masters degree in computational logic. Check out the section Course Materials and download the "course manuscript from 2004" - very, very cool stuff. I just wish I had enough time to work through it.

Finally there is some nice looking course material up at Stanford for their CS157 : Computational Logic course. This is probably a good place to start - check out the "readings" for what amounts to an online textbook in CL. There are exercises and exams too. Fun times.

Tuesday, January 25, 2011

Follow up on my last post on Dlanga

This is just a quick post to follow up on my last post that dealt with Khaya Dlanga's post on abortion and frivolity.

Jacques Rousseau of has written a solid, but critical, response that is well worth checking out.

I think Jacques has given a fair assessment of the failings of my reaction to Dlanga's post, while at the same time articulating an important dimension to the debate that was absent in my response (although was picked up, to a certain extent, by the comments on my piece).

Tuesday, January 18, 2011

A quick response to Khaya Dlanga's latest

I generally enjoy Khaya Dlanga's posts as they tend to be a breath of fresh, rational, and occasionally funny air on News24.

But in his latest column, in which he tackles the case of an Australian couple who aborted their twin foetuses because they happened to be male instead of the female that they were aiming for, he sorely disappoints.

He argues that their decision is "frivolous" - that their reasons don't carry the requisite "weight" (my words, not his) to be a reason to abort.
"To abort a child simply because they happened to be a wrong gender is beyond frivolous. If this is permitted, then where do we draw the line? If it were found, for example, that the baby would have green eyes as opposed to the blue that the parents wanted it to have, does that also mean this would be permitted?"
Perhaps their decision is frivolous? I'll have more to say about this below. However the first question we have to ask is why Mr Dlanga doesn't take the time to examine the question in the other direction? He's claims that edge cases like these lead us down a slippery slope to designer families. But what about the other slope? If we deny a woman the right to abort her pregnancy on the grounds that her reasons are frivolous "where do we draw the line" then? Who decides what counts as frivolous?

Well ... uh ... apparently ...
"This is the very reason I believe that States have the right to intervene."
Well, okay - but how can we guarantee that the state will make the kinds of choices that are in the best interest of the mother? How can we guarantee that the state wont use this kind of power to undermine the mother's right to determine what happens with and to her body? We can't, it's impossible. That is one of the the central problems. Furthermore, once we start careening down this other slippery slope, we open the floodgates to a boatload of problems that make so-called frivolous decisions to abort look tame by comparison.

Mr Dlanga goes on to say that
"What the parents have done raises a moral question; even amongst people who support abortion (even though I don't think anyone truly supports abortion because no one goes around bragging about their abortions)."
Supporting abortion - if by this he means being pro-choice - is not the same as heartily endorsing the act of abortion for fun and profit. Supporting abortion, as a pro-choicer, in no way commits one to the the notion that the act of aborting a foetus is a good thing, rather it commits one to the notion that a woman has the right to choose whether or not to see her pregnancy to term regardless of her reasons, frivolous or not.

We pro-choicers are pro-choice because we respect the rights of a woman to decide what happens with her own body as well as her right to determine her future prospects. We don't need to respect the woman who aborts her pregnancy because she (I'm hunting for a truly frivolous reason here) - say - would prefer to spend the time and money that she would have on raising a child to shop for shoes. We have to respect her right to make that choice, frivolous or not.

There is a very important parallel here between abortion and free speech - we don't need to respect what our critics say, what religious fundamentalists say, what "militant" atheists say - but we sure as hell have to respect their right to say it because we recognize that the alternative is far more dangerous.

Make sure you check out Tauriq Moosa's stellar reply to Dlanga.

Monday, January 10, 2011

Formal virtues

It's been a while since I've had the pleasure of thinking about modality in terms of possible worlds; here in South Africa there aren't too many opportunities for an undergraduate or honours philosophy student to do a lot of logic - that seems to be left to the computer scientists for the most part.

So I was very excited when I started reading Taylor and Dennett's treatment of possibility, necessity, and causation in chapter 3 of the Dennett's Freedom Evolves - essentially they present a way of thinking about these concepts in terms of possible worlds in order to show that our ordinary understanding of the words are pretty much neutral with regards to determinism or indeterminism - it's an enlightening discussion that, at least for me, clears up some of the conceptual terrain.

I don't actually want to talk about the content, but rather make a quick note about the presentation.

In his book, Dennett mentions that the chapter is that its content is basically a "gentler" version of the argument they put forward in Taylor and Dennett (2001).

What's so interesting is that parts of Freedom Evolves are lifted almost verbatim from the 2001 paper, with the major changes being that Dennett softens the presentation by pretty much removing all of the formalization by rewriting in ordinary English.

So what, in the 2001 paper, was rendered as

There exists (within some set X) a possible world in which the sentence "x (x is Socrates x has red hair)" obtains

is rendered in Freedom Evolves as

There is (at least one) possible world f in which the sentence "There is something that is Socrates and he has red hair" is true
The really cool thing is that by reading these two versions of what is essentially the same thing, one can really see how valuable formalization can be in philosophy.
Reading through the 2001 paper I was struck by just how much clearer it was than the rendering in Freedom Evolves. The formal renderings (without getting into argument's about just how conditionals are supposed to work) are just much more precise and leave a lot less room for misinterpretation.

I don't believe that philosophy should be a discipline where papers are exclusively written in arcane symbols, but in reading these two versions next to one another my conviction that Formal logic is an essential element in any thinking person's "mental toolbox" has been greatly strengthened. The Formal-logically-type-of items in this toolbox should at minimum include a basic understanding first-order logic, and - perhaps - just enough modal logic to get along.