I just saw that the latest “Philosophical Perspectives”:http://www.blackwell-synergy.com/toc/phpe/20/1 is out. I’m rather happy that my little “magnets paper”:http://www.blackwell-synergy.com/doi/abs/10.1111/j.1520-8583.2006.00116.x is in print. That’s in part because it is a paper that arose out of my Lewis seminar, and I’m happy that’s already led to one in print conclusion. And in part because I think the puzzle is so interesting.
The puzzle is probably simpler than I thought it was. (I’m indebted here to conversations with Robbie Williams.) If M1 and M2 are distinct fundamental vector-valued magnitudes, then intuitively (a) the direction of x’s M1 is not intrinsic to x, and the direction of x’s M2 is not intrinsic to x, but (b) the angle between x’s M1 and x’s M2 is intrinsic to x. That strongly suggests that a property that x has in virtue of two non-intrinsic properties it has is itself an intrinsic property. It is rather a strong restriction on theories of intrinsicness that it leave this open as a possibility. If I hadn’t thought about vectors, I would never have thought this was a possibility. But it is, and now I have a little paper in print saying why it is.
There look to be many other excellent papers in the volume, so when I’m finished grading, reviewing, meeting deadlines etc, I’ll try to say something about them. That may not be soon.