Today's show features Alison Gopnik on the Imagination. This is Alison's second visit to Philosophy Talk. Check out the show she did with us on Nature vs. Nurture. Since it's been awhile since I've done a pre-show blog, I thought I'd jot down a few initial thoughts before we take to the air.

First, thought. The imagination is a pretty cool thing, but also in some ways puzzling. On the one hand, it seems sometimes to give us cognitive acquaintance with real possibilities. A kid from Hope Arkansas imagines growing up to be president of the United States. And lo and behold that kid does grow up to be president. So some of the things that we merely imagine are really possible. And it's arguable that the imagination teaches us that they are possible.

On the other hand, I can imagine being able to fly of my own natural powers, or imagine being able to travel faster than the speed of light. But these things are not possible, at least not physically possible.

If even the impossible is imagineable maybe the imagination doesn't really have any intrinsic power to acquaint us with possibilities after all.

I doubt that's quite right, though. Take my being able to fly by my own natural powers, unaided by motors or wings. That is physically impossible. But maybe it's logically possible. Maybe when I'm imagining that what I'm gaining acquaintance with is a merely logical possibility.

Can we imagine things that are not even logically possible? Maybe, but I don't think we can imagine them very thickly or richly. But that may not say much about the limits of our imagination. Maybe there just isn't anything very much to imagining a logical impossibility. Or maybe in a way there's too much to imagining a logical impossibility. After all, in a logically impossible world literally everything goes. So there's nothing specific, as it were, to this or that logically impossible situation which would distinguish it from any other in our imagination.

Or look at the imagination from another side. Sometimes our imaginations are too constrained by the actual. In that case, the thing we need to do is to unleash the power of the imagination, to let it roam more freely. Remember Condi Rice saying that no one imagined that a group of terrorists might hijack an airplane and use it as a missle. Turns out she probably wasn't speaking the whole truth. But let's forget that for now. It certainly seems as though the folks in charge should really let their imaginations run wild. And if they fail to imagine things that might well happen -- especially if some of those possibilites do turn out to be actual -- we can justly criticize them for a failure of the imagination. Failures of imagination wouldn't be worthy of criticizing, I think, if we didn't think that through imagination we were getting at something real -- a real possibility.

Of course, maybe sometimes we imagine sort of idly, without any deeper cognitive purpose except to engage the imagination. We just kind of play with the imagination. I think kids do a lot of imaginative play, for example. But I don' t think it's at all cognitively idle. I think they are exploring the outlines of the moral universe, figuring out who and what they shall be, gaining acquaintance with a world of possibilities, some near to actual, some quite remote from the actual, gaining fuller acquaintance with the causal and counterfactual structure of the world. All really cognitively momentous stuff.

Philosophy is often an exercise in imagining. A characteristic sort of philosophical question is "how possibly" question. How possibly could a mind embued with rationality, intentionality, consciousness, will, and personhood be just a part of material nature? How possibly could free will subsist in a deterministic universe? How possibly could norms be determined by the facts alone?

To answer such questions, philosophers try to construct in imagination more or less richly characterized alternative possible worlds. And then they try to convince you that the constructed possible world is really not so terribly distant from our own. Or if they want to show that it is not possibly so -- not possible to locate mind in nature or to reconcile free will and determinism, for example -- then they try to show that there is no possible world plausibly like our own in which, say, the mind is just a material thing or free will and determinism co-exist. That too usually involves trying to gain fuller imaginative acquaintance with the totality of possible worlds. Search all the possible worlds in your imagination, you won't find one in which free will and determinism co-exist (except perhaps very remote worlds utterly unlike our own.).

Either way, the point is to try to gain fuller imaginative acquaintance with some set of possibilities and thereby to answer the how possibly question, whatever it was, with which we started.

This post is just to get the juices flowing for the show. I'm sure that after Allison and John enlighten me, I'll have many more thoughts.

Tchau for now.