Research

The book-length project I am engaged in is an analysis of what I take to be two different methods of reasoning; case-based reasoning (CBR) and rule-based reasoning (RBR).  I'm interested in this analysis for a number of reasons.

1. In machine learning there is explicit talk of these two approaches to machine learning but not a whole lot in the way of theoretical discussion of what ultimately differentiates the approaches (apart from obvious implementational differences).  Making the distinction clearer will have fruitful consequences at the level of machine modelling.

2. There is a good deal of interest in many different communities – AI, linguistics, philosophy -- in the idea of analogical reasoning, how we us metaphors, and so on, but again there isn't much at the theoretical level that explains how this kind of reasoning connects up with other kinds of reasoning.  Not surprisingly, we find that in analogical machine-learning systems, the active constraints are methodological and performance-based rather than theoretical.  I suspect that a theory of case-based reasoning will be foundational for work in analogical reasoning since, I think, analogical reasoning is a special kind of CBR.  Trying to create a system that reasons analogically using a rule-based approach is putting the cart before the horse, so to speak; because we have to figure out the constraints for the types of things that can be compared and the ways in which they can be compared before we know what we are interested in comparing, our rules will always fall sort of our requirements in a way precisely analogous to the way in which RBR in general falls short in those domains in which CBR is better situated.  So, analogical reasoning is a special case of the general CBR point. 

3.  Finally, my hunch is that an implicit appeal to these two fundamentally different ways of reasoning underlies the polarising debates in many different disciplines – linguistics, cognition, ethics – and that by making these commitments explicit, the debates might be resolved through discussion of these more fundamental issues.  Ultimately, I'm interested in shedding light on the debate between the cognitivist and the embodied theorist in cognitive science, but I've begun by writing a paper that on what I take to be the parallel debate in ethics between moral generalism and particularism.  

Research Project:

I'd like to test out some of my suggestions in this paper by developing a CBR system using a connectionist network that is trained to make moral judgements.  Anyone interested in doing collaborative work in this or a similar area should e-mail me here.