Keith Wiley shared a link. 12 Dec

I'm posting/linking this recent talk by Susan Schneider (with whom I have had a small amount of correspondence, and would love to continue, but I suspect she's too busy) just so I can post my response, as follows:

I wish Susan Schneider would be a little more open minded about branching identity. She and I traded a tiny amount of conversation a few years ago (very civil) and she said she would read my book, but I have my doubts she ever actually did. I'm sure she's very busy, but the truth is, I don't think she has considered the topic carefully (no disrespect), or at least fairly.

Meanwhile, for years, including her most recent public talks, such as the linked video, she still presents the classic reduplication (what a horrible term, not her coinage of course) thought experiment (tantamount to nondestructive mind uploading or multi-instantiation mind uploading) as an obvious and conclusive deathblow to mind uploading in general.

She commits multiple errors (by my reasoning) repeatedly in her discourse on the issue. First, she makes a classic substance dualism error in questioning "how the mind or identity or consciousness" *moves through space* to the upload's new brain/computer or body/robot. This is an obvious substance dualism implication, the notion of some ethereal extra stuff that needs to get from the head to the computer in order to allow a judgment of successful identity preservation (this is why I don't even use the term "identity transfer" because "transfer" again implies motion through space by some metaphysical substance, which I consider a category error on this issue). Pattern identity, which she alludes to in her talks, but generally argues against for the reason given above, suffers no substance dualism aspect, which is why I find it so favorable.

Second, she repeatedly argues against uploading by imagining waking up after a nondestructive procedure and taking a person's "feelings about themselves" as informative testimony. She presumes, without explanation, that the experience of waking up afterward *must* be interpreted from the point of view of the person and body who preceded the procedure, what we often call the "original" (admittedly the physical or body original, but not conclusively the psychological original since that is the subject of debate! Carts before horses folks.). A lot of people make this error of judging uploading from the point of view of the bio-original, but it is particularly vexing to hear it from a philosophy professor! I intend no disrespect, but she should know better. She won't fairly interpret the same scenario through the eyes of the upload as he or she awakens. We all know how this thought experiment plays out. The upload feels the same visceral sense of identity (and identity continuity) with the person who preceded the procedure, putting us in a paradox of identity claims Since both participants' personal feelings (and verbal self-reports) will be identical, we cannot take such feelings and reports as informative. We must look elsewhere for our answers. To favor the bio-original would require resorting to body identity (which Parfit has already thoroughly rejected for us). In other words, Schneider is simply biased on this thought experiment. She imposes a bias that favors one person over the other, and there is no a priori justification for the bias. She simply adopts the bias and then states the conclusion that would follow from it. But the initial bias is not itself justified by an external or objective motive. She tries though, in her presentation of space-time-worm identity, presented below, but if she would rely on that explanation to support her argument anyway, then why even bother presenting the flawed personal point-of-view argument above? She should just discard that argument entirely and jump straight to other theories.

Her third argument that keeps coming up is a space-time-worm (STW) theory of identity, which claims that people (and their brains and their minds and their metaphysical identities) *must* follow a contiguous path through 4D space-time. It is true that up to the current point in history, persons (human minds and identities) have all followed the STW pattern, but that observation doesn't in itself prove the necessity of a STW requirement. It is not necessarily required by external metric just because we have observed it in the cases currently available for consideration. This is a failure of symbolic logic frankly: the observation of A only under the circumstances of B does not, in itself, prove the necessity of B for all cases of A.

Consider an analogy that illustrates this point: Alice has only ever seen red apples. So, she concludes redness is a defining property of an apple. By her reasoning, apples aren't incidentally red, they *must* red since apparently they all are. But of course, we know that Alice is incorrect, there are green apples she has never seen. One might counter-argue that green apples still exist even if she hasn't seen them, but that doesn't follow because, of course, in the evolution of the apple, the first species or variety was most likely some particular single color, let's say red. Should we have concluded all apples must be red? Other colors of apple eventually arose in the evolutionary timeline. One might counter argue that apples were all "defined" as red so long as they all actually were red, but then the definition broadened when green apples first evolved. To which I would respond: In that case, STW identity only holds for that early portion of history when nonSTW identity was not technically feasible, but as soon as we achieve the technology to do it, STW identity prescribes no prohibition. Rather, the definition of identity (and identity continuity) simply conforms at that time to a broader definition, thereby invalidating Schneider's point.

What is missing from Schneider's STW identity theory is any proposal of a causal, physical, or otherwise necessary explanation. It is imposed as a means to explain away paradoxes that otherwise arise. STW identity is merely proposed to posteriori "clean up the problems", but without any a priori necessity. It is just a retroactive attempt to make a philosophical paradox go away.

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