Hofstadter, Dennett - The Mind's I

A Conversation with Einstein’s Brain 441TORTOISE: Well, you came up with a good thought. That's just what we'd try toimplement, had we the book.ACHILLES: So, you mean, we'd look up the possible changes in Einstein's auditoryneuron structure resulting from each tone of the utterance?TORTOISE: Well, roughly. You see, we'd have to do it very carefully. We'd take the firsttone, as you suggested, and see which cells it would make fire, and how. That is,we'd see precisely how each number on each page would change. Then we'd gothrough the book painstakingly page by page, and actually effect those changes.You might call that "round one."ACHILLES: Would round two be a similar process occasioned by the second tone?TORTOISE: Not quite. You see, we haven't completed the response to the first tone yet.We've gone through the book once, neuron by neuron. But there is the fact thatsome of the neurons are firing, you know, so we have to take that into account.Which means we have to proceed to the pages where their axons lead and modifythose pages in the way that is directed by the "structure-changing numbers." Thatis round two. And those neurons, in turn, will lead us to still others, and lo andbehold, we're off on a merry loop around the brain.ACHILLES: Well, when do we ever come to the second tone?TORTOISE: Good point. It's something I neglected to say earlier. We need to establish akind of time scale. Perhaps on each page the time taken for the neuron in questionto fire is specified-the time it took to fire in real life, in Einstein's brain-a quantitybest measured, probably, in thousandths of a second. As the rounds progress, wesum up all the firing times, and when the times add up to the length of the firsttone, we start in on the second tone. That way, we can proceed to feed in toneafter tone of your self-introductory utterance, modifying the neurons that wouldrespond to that utterance at every step along the way.ACHILLES: An interesting procedure. But surely a very lengthy one.TORTOISE: Well, as long as it is all hypothetical, that should not bother us in the least. Itwould probably take millennia, but let's just say five seconds, for the sake ofargument.ACHILLES: Five seconds required to feed in that utterance? All right. So right now, mypicture is that we have altered scores, if not myriads, of pages in that book,changing numbers, on page after page after