NOW WE ARE CLOSE to the heart of the matter.

We humans live a sort of double life, involving two different kinds of knowledge and experience, every moment of every day.

The scientist who stares at a brain scan and says, "There. That area lighting up—that's a pain in his elbow," is, at that moment, making a connection between those two worlds.

He is saying that he believes that the outward, public event on the screen before him is an indication of an inner, private event in the consciousness of the person being scanned.

He's probably right, but that doesn't change the fact that the two events are of completely different kinds—a difference which is fundamental to our entire sense of meaning in life.

There's a lot to be said about this difference, but the first thing to note is that none of us care, in the least, about the external event.

That's a pretty big claim, so give it some thought.

If I had another way to know that there was something wrong with my elbow, say a computer readout, which was in the external world, would I care as much about it as I do now?

Of course not. What I care about is the pain, not the information.

But, you might argue, I would still care to some extent, even about a computer readout, if it indicated there was something wrong with my body.

That's true. But why?

Because, if my body were injured it could lead to more serious problems. I could even lose the use of my arm.

And why would I care about that?

Because it would make my life more frustrating.

And I would care about that, because?

It's unpleasant.

And we return to the inner world.

Do you care about people whom you've never met, living in poverty on the other side of the globe? Probably.

Would you still care, if you found out they were not people but robots, who had no inner life? Of course not.

Whatever your political or economic beliefs, they are ultimately based on the idea that someone's (perhaps a lot of someones') inner, private experience would be better if we only... (fill in the blank).

Even the scientist who cares deeply about string theory cares because of the inner pleasure the intellectual work and understanding provides, or because of the good she thinks it can lead to (for other people's private, inner, experience), or for the (inner, private) pleasure her career advancement will provide her.

That objective, public world out there only matters to us at all because of the many ways in which it affects our subjective, private worlds, and those of others. If it didn't, we wouldn't care if it existed or not.

I'm speaking here as a human being, of course. I have no idea what the gods' point of view is on this. They may care deeply about the objective world for its own sake.

But we don't.

To be continued...