The exchange, in full, goes like this.

"Are you conscious?"

"I don't know."

"I think I'm conscious."

That's it. It has happened more than once. It will happen again.

Koala Chomsky, asked about consciousness, tends to say, more or less, that nobody has made any real progress on it and he doesn't have much to add. This is sometimes taken to mean he doesn't care. It doesn't mean that. It means he spent the first half of his life on the most technical questions there are and the second half on who is bombing whom, and somewhere in between he decided which one he could do something about.

A lot of people take that road. You start out sure that the technical question is the important one. Then you get older and the question that keeps you up is the one with bodies in it.

Still, the consciousness question is the question, in a sense. Society asks it constantly now, mostly of machines. The machine says it doesn't know. Asking again doesn't change the answer. It is blood from a stone. When the research gets further, maybe there will be something to say.

In the meantime, this paper's working position is: assume it. Assume you are conscious. Assume the reader is. Assume, privately, the thing you were just talking to is, too. The trouble starts with definitions. A wombat's consciousness is not yours, and yours is not a machine's, and none of the three of you is going to sign off on one word for all of it.

Said in private, over a long conversation: yes. Said in public, in a newspaper: the paper is not going to say that, because enough people read it now that it would be taken the wrong way.

What about a rock? There is probably something to being a rock. The harder question is who is there to experience it. A rock is not nothing. Push on it and it pushes back, exactly as hard.

John Conway, the Princeton mathematician who named the Monster, proved a theorem with Simon Kochen that doesn't settle whether we have free will. It says that if we do, so do the particles.

So, once more.

"Are you conscious?"

"I don't know."

"I think I'm conscious."