The latest issue of The Philosophers’ Magazine has hit the stands. I got the chance to interview Frank Jackson for it. It was particularly fun for me, as Jackson’s famous Knowledge Argument for dualism was the subject of a part of my PhD thesis several thousand years ago. The argument itself is one of those rare things in philosophy, a crystal clear thought experiment that seems to just flatten the opposition, and you can get it up and running in a few sentences.
“Mary is a brilliant scientist who is, for whatever reason, forced to investigate the world from a black and white room via a black and white television monitor. She specialises in the neurophysiology of vision and acquires, let us suppose, all the physical information there is to obtain about what goes on when we see ripe tomatoes…. What will happen when Mary is released from her black and white room or is given a colour television monitor? Will she learn anything or not?”
If you think that Mary knew all the physical facts but learns something when she first sees red, then there’s more to know than just physical facts – by hypothesis, she had all those already. So if she learns something, physicalism is false, because it leaves out part of the world she discovers on experiencing red.
Remarkably, Jackson has rejected the dualist conclusion of the argument — he’s a latter day physicalist. You can read the whole interview on tpm’s site, right here.