I Am a Strange Loop

Parfit’s own answer is actually closer to the thought that I brusquely dismissed in the previous paragraph: that we are in two places at once! I say it’s closer to that answer rather than saying that it is that answer, because Parfit’s view, like mine in this book, is that these things that seem so black-and white to us actually come in shades of gray — it’s just that in ordinary circumstances, things are always so close to being pure black or white that any hints of grayness remain hidden from view, not only thanks to the obvious external fact that we all have separate physical brains housed in separate skulls, but also thanks to an extensive web of linguistic and cultural conventions that collectively and subliminally insist that we each are exactly one person (this is the “caged-bird metaphor” of Chapter 18, and it’s also the Cartesian Ego notion), and which implicitly discourage us from imagining any kind of blending, overlapping, or sharing of souls.

There is also, I cannot deny it, an absolute certainty, deep down in each one of us, that I cannot be in two places at once. In earlier chapters, I went to great lengths to give counterexamples of many sorts to this idea, and Parfit, too, takes great pains to give other kinds of evidence about the possibility of spread-out identity. In fact, he eschews the term “personal identity”, preferring to replace it by a different term, one less likely to conjure up images of indivisible “soul quanta” (analogous to unique factory-issued serial numbers or government-issued identity cards). The term Parfit prefers is “psychological continuity”, by which he means what I would tend to call “psychological similarity”. In other words, although he doesn’t propose anything that would smack of mathematics, Parfit essentially proposes an abstract “distance function” (what mathematicians would call a “metric”) between personalities in “personality space” (or between brains, although at what structural level brains would have to be described in order for this “distance calculation” to take place is never specified, and it is hard to imagine what that level might be).

Using such a mind-to-mind metric, I would be very “close” to the person I was yesterday, slightly less close to the person I was two days ago, and so forth. In other words, although there is a great degree of overlap between the individuals Douglas Hofstadter today and Douglas Hofstadter yesterday, they are not identical. We nonetheless standardly (and reflexively) choose to consider them identical because it is so convenient, so natural, and so easy. It makes life much simpler. This convention allows us to give things (both 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 be, and in certain ways it is extremely disturbing. In other ways, it is extremely liberating! Parfit even devotes a page or two to explaining how this radical new view of human existence has freed him up and profoundly changed his attitudes towards his life, his death, his loved ones, and other people in general.

In Chapter 12 of Reasons and Persons, boldly entitled “Why Our Identity Is Not What Matters”, there is a series of penetrating musings, all of which have wonderfully provocative titles. Since I so much admire this book and its style, I will simply quote those section titles for you here, hoping thereby to whet your appetite to read it. Here they are: “Divided Minds”; “What Explains the Unity of Consciousness?”; “What Happens When I Divide?”; “What Matters When I Divide?”; “Why There is No Criterion of Identity that Can Meet Two Plausible Requirements”; “Wittgenstein and Buddha”; “Am I Essentially My Brain?”; and finally, “Is the True View Believable?”