It is, I think, significant that writers on personal identity often tell stories about mad surgeons who make changes in our memories or characters. These writers usually emphasize the fact that after the surgical intervention we are altered, we have changed. But surely part of what creates the sense of lost identity is that the person is changed by intervention, from outside. The stories might affect us differently if we imagined the changes initiated by the person herself, as a result of her own choice. You are not a different person just because you are very different. Authorial psychological connectedness is consistent with drastic changes, provided those changes are the result of actions by the person herself or reactions for which she is responsible.She then states the broader thesis that these reflections serve: “the sort of continuity needed for what matters to me in my own personal identity essentially involves my agency” (123).
However, drastic changes that are fully intended consequences of one's own agency can similarly disrupt one's personal identity. Consider the following story:
Yawgmoth was the cruelest of demons, and he liked tormenting the damned. But his greatest wish was to leave Hell and wreak horrible misery upon the happy people living above. He knew why no demon had ever done such a thing – the gates of Hell were enchanted so that only a creature of pure benevolence could exit. So he learned how to make a potion that would wipe all the malevolence from his mind and replace it with benevolence just for one minute, allowing him to leave and then become cruel again. He poured it into a goblet, strode to the gates, and drank.Intuitively, Yawgmoth becomes a different person after drinking the potion, no less than Dr. Jekyll or any victim of a mad surgeon. That he intends this change and is responsible for it does not make him the same person before and after.
But what happened then? Having become a creature of pure benevolence, he recoiled at the horrors that the living would endure if the cruelest demon of Hell was among them. Instead of passing through the gates, he ran back into Hell. And wishing to spare even the damned from the torments of a furious and frustrated Yawgmoth, he bravely pulled a cleaver from the hands of another demon, struck off his own head, and perished.
This is not to reject Korsgaard's broader thesis that personal identity has some interesting esential relation to agency. Nor is it to say that intentionally causing the changes in oneself is wholly irrelevant to personal identity – just that it is one among many more or less significant sorts of psychological connectedness.