Saturday, October 16, 2010

Thinking about my appendix

Fairly famously, Russell thought that you could only have singular thoughts about things you were directly acquainted with. For Russell this meant you could only have singular thoughts about your present experiences and maybe yourself. Nobody thinks that anymore, but we do mostly agree that Russell was on to something. If there’s a guy in Wisconsin called Hank that I’ve never met, I can’t think about him because I don’t know about him. I can wonder generally about whether there’s a guy called Hank and he’s happy, but I can’t wonder whether Hank himself is happy. I can’t think about people I don’t know about (in the relevant sense of ‘know about’).

Now, I’ve never seen my appendix, and hopefully I never will. I don’t even really know where it is. I can’t feel it, and I’m not aware of it doing anything. But I’m pretty sure I can think about my appendix. I can wonder where it is, what it looks like, and whether it’s one day going to kill me.

One explanation for my ability to think about my appendix is that I know I’ve got one, and only one. If I’m acquainted with something, and I know it’s got one and only one of something, then I can think about the second thing via the first. I know about Russell and I know he had exactly one mother, so I can think about Russell’s mother via Russell. That doesn’t sound too crazy a result.

It does come out awfully permissive, though. Presumably my red blood cells are all slightly different sizes, so I’ve got exactly one largest red blood cell, so I can think about that. In the same way I can think about the oldest man in Hawaii, the first child born in the 22nd century (who Kaplan called ‘Newman I’), the centre of gravity of the Pacific Ocean and other such tenuous acquaintances. In fact I can think about the satisfier of any definite description I know to be satisfied, through my acquaintance with the world. I can think about the shortest spy, even if the shortest spy is an alien on another planet.

Now you can say that in these cases only the thing I’m acquainted with directly sits in the content of the thought, so when I’m thinking about the shortest spy I’m really just thinking about the universe or spies in general, and when I’m thinking about Clinton’s mother I’m really just thinking about Clinton and mothers in general. Perhaps that’s right. But then I never really think about my appendix either. What I’d like to do is find a principled way of drawing the line somewhere between my appendix and the shortest spy, and I don’t know how to do that.


  1. You seem to have devised a spectrum of things that you can think about - with your appendix at the definite end and things that aren't in your body at the other end.

    But I'm not sure this is an accurate way of characterising things. For a start, I don't think you can genuinely think about your appendix. What if you were subject to an (unknown to you) genetic anomaly and had two? Doesn't this mean that when you think your one appendix you are thinking about a fictional construct?

    In which case isn't thinking about appendix in the same class as all the other things you cite?

    In which case, Russel starts to look quite convincing.

  2. I agree that if I had two appendices, then I wouldn't know I'd got exactly one and I couldn't think about either. But I think that in the ordinary sense I do more or less know I've only got one, I can think about it, and I sometimes do. You can raise doubts about anything: if I'm a brain in a vat then my bedroom's a fictional construct, but since I'm not and it's not I can think about my bedroom.

    But Russell's view does look a lot neater when the things you can think about are just things like experiences, for exactly this reason.

    One problem with it is that on a lot of people's view of the mind you can be wrong about what experiences you're having, but another problem is that there's an everyday distinction between the things we can think about and the things we can't. Russell's position is revisionist but makes sense from a sceptical point of view, but if we're not sceptics we still want a way of capturing the distinction. I guess some borderline cases will be up for grabs to the neatest theory, but I can't see a principled way of drawing the line which isn't very revisionist indeed.