Terlassie passing the finish
Some time ago I criticized in a blog that philosophers using thought experiments often don’t realize that the assumptions of such an experiment can push the answer in a certain direction. In my last blog I criticized that in thought experiments the context often is left out, although it can be highly relevant for what we want to show in the experiment. Maybe there are more mistakes in thought experiments that I failed to notice. Who knows, for I have never made a systematic study of the subject. These were just two flaws that caught my eye.
Even so, I don’t want to say that thought experiments are useless but only that they bear the seed of misrepresentation within them and that they can be misleading. For there are also a lot of interesting and important philosophical thought experiments. And, to be honest, isn’t it just fun to think up a good one and to tease your mind with it? Isn’t just that one reason why we philosophize? One of the most famous thought experiments has laid even the foundation of modern western philosophy: Descartes’ evil demon (Descartes wondered whether his thoughts weren’t misled by a devil; or, in other words, whether his senses did not give him a complete illusion of the external world. He concluded that anyway his thinking activity could not have been misled). Used with insight, thought experiments can bring us a step forward or make us things clear. So, the British philosopher Elizabeth Anscombe used one for showing that in concrete situations it is not possible to delimit a person’s actions: What an action is is a matter of perspective. When I flip the switch, do I turn on the light in the room or do I warn the thief in my house? (the example is Davidson’s) If the thief left no traces and took nothing with him, I’ll never get the idea to use the latter description but only the former. This thought experiment shows also that actions can have side effects.
I think that in situations where assumptions and context play no fundamental role, thought experiments can be appropriate. That’s also the case when they are used for undermining arguments. This makes Searle’s Chinese Room thought experiment so strong and to the point (http://en.wikipedia.org/wiki/Chinese_room). In this way, once I have used a thought experiment for refuting the idea that the person only goes where the brain goes and that brain and body can be separated, as is implicit or explicit in many theories on personal identity in the analytical philosophy, the so-called psychological identity theories (like the one defended by Parfit). Here I’ll present it in a new version:Two marathon runners, Haile Gebrselassie and Paul Tergat, have switched bodies, so that the brain of Gebrselassie and the body of Tergat belong together and the other way round (let we call them Gebregat and Terlassie respectively). They take part in the same race, but Gebregat leaves the race injured while Terlassie wins. Then, since the person goes where the brain goes according to psychological identity theorists, it is Paul Tergat who has won the race, although it was Haile Gebrselassie’s body that passed the finish line first and although Paul Tergat’s body could not withstand the strain of the race and even didn’t finish. So, if we may believe the psychological identity theorists it is not the body that runs but the brain. For how else could it have been that Paul Tergat had won?