Carving up the philosophical terrain around personal identity a little differently

Warning: I haven’t studied personal identity since a single undergraduate subject, so I’m guessing this distinction already exists in the literature and I just didn’t find it with a cursory search, I claim no originality for this, and if someone can find a source, let me know so I can give credit.

Many people are aware that there is a debate between the psychological and bodily continuity theories of personal identity over time. I want to carve up the logical landscape in a way which introduces a second, fully independent axis substantive vs pattern continuity. According to the substantive view of personal identity, you survive if whatever object makes you up survives. According to the the pattern continuity view, you survive if the pattern that you consist in continues, even if that means destruction of the object that currently instantiates the pattern which makes up you, followed by its replacement with an object that continues that pattern. The substantive view is often conflated with the bodily view, and the pattern view is often conflated with the psychological continuity view, but as we will see, such they are conceptually independent.

In order to demonstrate this, let’s consider two classic cases which, when considered jointly, none of the four possible combinations (bodily substantive, psychological substantive, psychological pattern and bodily pattern) gives the same array of answers to:

1. A brain transplant

If your brain is placed in a new body and your old body is destroyed, have you effectively “changed bodies”, or have you simply died?

According to both psychological views of identity (pattern & substantive) you survive a brain transplant in which your initial body is discarded. According to both bodily views of identity (pattern & substantive), you do not, since you are constituted by your whole body, not just your brain. So far we are in agreement with the standard account which treats all psychological theories as pattern theories and all bodily theories as substance theories.

2. Teleportation

If you are annihilated, then reconstructed elsewhere by a teletransporter, have you survived?

Here’s where we diverge from the normal account. Teleportation is often thought to separate the bodily and psychological continuity theories of survival, with the psychological view contending that one survives teletransportation and the bodily view contending that one does not. Instead, on our taxonomy, what this case really separates is the pattern and substantive axis of views on personal identity. According to both pattern views of identity (bodily and psychological) you survive teleportation. In both cases the pattern or arrangement that, according to these views, consists in who you are, is continued, since the pattern of both body and mind is recreated. Also in both cases, the substance of what you are (either the actual mental states instantiated in the brain, or the whole body) is destroyed, so both substantive views (bodily & psychological) rule this is a case of death.

Thus we see that the four possible combinations of views in our taxonomy are logically distinct, because none of them give the same answers as another to both cases above. The bodily substantive theory holds that one survives in none of these cases, the psychological substantive theory holds that one survives in the case of a brain transplant, but not teleportation, the bodily pattern theory holds that one survives in the case of teleportation but not a brain transplant and the psychological pattern theory holds that one survives in both cases.

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