animate and inanimate) fixed names and to talk about them from one day to the next without constantly having to update our lexicon. Moreover, this convention is ingrained in us when we are infants — at about the same Piagetian developmental stage as that in which we learn that when a ball rolls behind a box, it still exists even though it’s not visible, and may even reappear on the other side of the box in a second or two!
The Radical Nature of Parfit’s Views
To dismantle unconscious beliefs that are so deeply rooted and that have such a degree of primacy in our worldview is an extremely daunting and bold undertaking, comparable in subtlety and difficulty to what Einstein accomplished in creating special relativity (undermining, through sheer logic, our deepest and most unquestioned intuitions about the nature of time), and what a whole generation of brilliant physicists, with Einstein at their core, collectively accomplished in creating quantum mechanics (undermining our deepest and most unquestioned intuitions about the nature of causality and continuity). The new view that Parfit proposes is a radical reperception of what it is to
In Chapter 12 of
Even though all eight of these sections are rife with insight, it is the last section that I admire the most, because in the end, Parfit asks himself if he really believes in the edifice he has just built. It is as if Albert Einstein had just realized that his own ideas would bring Newtonian mechanics crashing down in rubble, and then paused to ask himself, “Do I really have such deep faith in my own mind’s pathways that I can believe in the bizarre, intuition-defying conclusions I have reached? Am I not being enormously arrogant in rejecting a whole self- consistent web of interlocked ideas that were carefully worked out by two or three centuries’ worth of extraordinary physicists who came before me?”
And although Einstein was exceedingly modest throughout his lifetime, his answer to himself (though to my knowledge he never wrote any such introspective essay) was, in effect, “Yes, I do have this strange faith in my own mind’s correctness. Nature
Self-confidence, Humility, and Self-doubt
Parfit is far more prudent than this. His conclusions, to my mind, are just as radical as those of Einstein (although I find it a bit of a stretch to imagine radical ideas about the ineffability of personal identity leading to any marvelous technological consequences, whereas Einstein’s ideas of course did), but he is not quite as convinced of them as Einstein must have been. He feels confident, but not absolutely confident, of his edifice of thought. He doesn’t think it will start to shake and soon tumble down if he stands on it, but then again he admits that it just might do so. Let us hear him express himself on this topic in his own words:
[The philosopher of mind Thomas Nagel] once claimed that, even if the Reductionist View is true, it is psychologically impossible for us to believe this. I shall therefore briefly review my arguments given above. I shall then ask whether
[A few pages later] .…I have now reviewed the main arguments for the Reductionist View. Do I find it impossible to believe this View?
What I find is this. I can believe this view at the intellectual or reflective level. I am convinced by the arguments in favour of this view. But I think it likely that, at some other level, I shall always have doubts.…
I suspect that reviewing my arguments would never wholly remove my doubts. At the reflective or intellectual level, I would remain convinced that the Reductionist View is true. But at some lower level I would still be inclined to believe that there must always be a real difference between some future person’s being me, and his being someone else. Something similar is true when I look through a window at the top of a sky-scraper. I know that I am in no danger. But, looking down from this dizzying height, I am afraid. I would have a similar irrational fear if I was about to press the green button.
….It is hard to be serenely confident in my Reductionist conclusions. It is hard to believe that personal identity is not what matters. If tomorrow someone will be in agony, it is hard to believe that it could be an empty question whether this agony will be felt by
I must say, I find Parfit’s willingness to face and to share his self-doubts with his readers to be extremely rare and wonderfully refreshing.
Morphing Parfit into Bonaparte
In the last paragraph quoted above, Parfit alludes to a thought experiment invented partly by philosopher Bernard Williams and partly by himself (in other words, invented by a Williams–Parfit hybrid who might be called “Bernek Willfits”), in which he is about to undergo a special type of neurosurgery whose exact nature is determined by a numerical parameter — namely, how many switches will be thrown. What do the individual switches do? Each one of them converts one of Parfit’s personality traits into a different personality trait belonging to none other than Napoleon Bonaparte (and I literally mean “none other than”, as I will shortly explain). For example, one switch makes Parfit far more irascible, another switch removes his repugnance at the idea of seeing people killed, and so forth. Note that in the previous sentence I used the proper noun “Parfit” and the pronoun “his”, which presumably is an unambiguous reference to Parfit. However, the whole question here is whether or not such usages are legitimate. If switch after switch were thrown, converting Parfit more and more into Napoleon, at what stage would he — or rather, at what stage would
As I have already made clear, asking exactly where along the line the switchover would take place makes no sense from Parfit’s point of view, for what matters is psychological continuity (
In Parfit’s view, the Cartesian Ego of Napoleon is not indivisible, nor is that of Derek Parfit. Rather, it is as if there were a slider on a wire, and the two individuals (who are
Most people, unlike Parfit, want there to be and are convinced that there