computer science

I spent the first part of my life in South Africa, where I met my wife Leta at the University of Port Elizabeth. After I gained an MSc in 1975 we moved up to the Rand Afrikaans University in Johannesburg so that I could do my PhD under the supervision of Johannes Heidema, South Africa's foremost logician and a thoroughly nice bloke with whom I have maintained a friendly research collaboration ever since. After a postdoctoral year in the USA and a couple of years roughing it at the University of Venda in the dusty heat of Thohoyandou, Venda, I became first an associate professor (1986) and then professor (1994) in the Department of Computer Science and Information Systems of the University of South Africa.

One chapter of my life began to draw to a conclusion and another to open during 1998. At the graduation ceremony on 12 May 1998 the University of South Africa conferred on me the honour of delivering the Chancellor's Address. In August 1998 I visited the University of Otago at the invitation of the then Head of Department, Brian Cox, whose old-world courtesy left a profound impression. And so in January 1999 Leta and I arrived in New Zealand, accompanied by our children, Jacques and Lisa. We're very happy in the friendly environment of Dunedin, which has the best weather in the world and no snakes, scorpions or baboon spiders. The departmental environment is harmonious, my colleagues are interesting, and the students I've taught here at Otago have been a pleasure to get to know. In 2002 we officially became Kiwis, to our delight.

Well, I say the weather's great in Dunedin. Of course, it gets pretty stimulating in winter and it is not just the rude glow of health in the cheeks but also humour that is stimulated. I went home one grey winter's day, wearing my usual walking clothes of khaki shorts, sleeveless polar fleece vest, and in deference to the south wind a long-sleeved shirt. On the way I encountered an elderly gentleman who was bundled up to the ears in coat, scarf, and hat. He looked at me and said "Don't you have a short-sleeved shirt?" I thought that was pretty funny.

My research is in applied (i.e. agent-oriented) logic and includes topics such as nonmonotonic entailment, defeasible reasoning, belief revision, introspection, categorisation, and the role of emotions in cognition. I am grateful to have such pleasant research collaborators as Johannes Heidema (University of South Africa) and Tommie Meyer (University of New South Wales) as well as my esteemed colleagues in the Artificial Intelligence Research Group.

I don't like travelling, particularly by air — airlines treat people like sheep and airports are degrading environments. As a consequence I don't go to conferences very often anymore. Fortunately my friends don't seem to mind travelling.

I support the Budapest Open Access Initiative, the Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities, and the Free Software Foundation.