Likewise, why should we abandon our commonsense attitudes about how many souls inhabit our brains when we know very well that the answer is just one? The only answer I can give is that, yes, the answer is very close to one, but when push comes to shove, we can see small deviations from that accurate first approximation. Moreover, we even experience such deviations all the time in everyday life — it’s just that we tend to interpret them as frivolous illusions, or else we simply ignore them. Such a strategy works quite well because we never approach the “speed of light” where the naïve, caged-bird picture fails badly. Less metaphorically, the lower-resolution, coarse-grained souls who fight and squabble for the chance to inhabit our brains never really pose any serious competition to “Number One” for the overall command, and so the naïve old caged-bird dogma “One brain, one soul” stands unchallenged nearly all of the time.
Where Does a Hammerhead Shark Think it is?
Perhaps the most forceful-seeming challenge to the thesis that a single soul — your own, say — is parceled out among a number of distinct brains is simply the question, “Okay, let’s suppose that I’m somehow distributed over many brains. Then which one do I actually experience? I can’t be simultaneously both here and there!” But in this chapter I have tried to show that you can indeed be in two places at the same time, and you don’t even notice anything funny going on. You can be in Bloomington and in Stanford at the same time. You can be in a Donner Pass ski lodge and a Midwest town’s kennel play area at the same time. You can be in your living room’s plush armchair and in an uncomfortable carriage bouncing along a nineteenth-century English country road at the same time.
If these examples are too far-fetched or too technological for your taste, then just think of the lowly hammerhead shark. The poor thing has eyes on opposite sides of its head, which look out, quite often, on two completely unrelated scenes. So which scene is the shark really seeing? Where does it consider itself to be, really? Of course no one would ask such a question. We just accept the idea that the shark can “sort of” be in those two different worlds at the same time, mainly because we think to ourselves that no matter how different those scenes look, they nonetheless are contiguous pieces of the underwater world in the shark’s vicinity, so there is no genuine problem about whereness. But this is glib, and sidesteps the point.
To put things in somewhat sharper focus, let’s invent a variation on the hammerhead shark. We’ll posit a creature whose eyes are taking in one situation (say in Bloomington) and whose ears are taking in another, unrelated situation (say in Stanford). The same brain is going to process these inputs at the same time. I hope you won’t claim that this is an impossible feat! If that’s your inclination, please first recall that you drive your car while reacting to other cars, scenery, billboards, and roadsigns, and also while talking with a far-off friend on your cell phone (and the topics covered in the conversation may vividly transport you to yet other places), and all during that very same period a recently-heard tune is running through your head, your strained back is bugging you, you smell cow manure wafting through the air, and your stomach is shouting to you, “I am hungry!” You manage to process all those different simultaneous worlds perfectly well — and in that same spirit, nothing is going to prevent a human brain from dealing simultaneously with the two unrelated worlds of Stanford sounds and Bloomington sights, no more than the hammerhead shark’s brain protests, “Does not compute!” So the idea “I cannot be simultaneously here and there” goes down in flames. We are simultaneously here and there all the time, even in our everyday lives.
Sympathetic Vibrations
But perhaps you feel that what I’ve just described doesn’t address the question originally posed about which of many brains you are really in — that being either here or there means that no matter how emotionally close you are to someone else, their feelings are always theirs, yours are always yours, and never the twain shall meet. This is once again the caged-bird imagery with which the chapter opened, and it will certainly not cease to rear its ugly head no matter how many times I try to cut it off. But let us nonetheless try tackling this medusa in yet another fashion.