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
The Radical Redesign of Douglas R. Hofstadter
The intuitions being pushed here are very emotional and run very deep in our culture and our whole view of life. It gets particularly intense for me when I insert myself into this scenario and start imagining the personality-trait substitutions that a neurosurgeon might carry out by throwing one switch after another.
For example, I begin by imagining that, upon the throwing of Switch #1, my love for Chopin and Bach is replaced by a visceral loathing of their music and that instead, a sudden yet powerful veneration for Beethoven, Bartók, Elvis, and Eminem flowers in “my” brain.
Next, I imagine that Switch #2 causes me every single weekend (and every other spare moment as well) to elect, instead of designing ambigrams or working hard on my book about being a strange loop, to spend hours on end watching professional football games on a huge-screen television and delightedly ogling all the busty babes in the beer ads.
And then (Switch #3) I imagine my political leanings being turned on their head, including my decades of crusading against sexist language. Now, I come out with “you guys” every other sentence, and anyone who objects to it I chortlingly deride as “a politically correct monkey” (as you might imagine, that’s just one of the milder epithets I use).