Therefore, one could argue that the idea of an “individual” existing through time has no objective basis to begin with, and the decision to identify entities that exist in different instants of time as the same “individual” can’t be other than a subjective whim.
Evolution may have reasons for making us think this, but how would you get that the identification of an individual existing through time is subjective? You can quite clearly recognize that there is a being of approximately the same composition and configuration in the same location from one moment to the next.
Even (and especially) with the Mach/Barbour view that time as a fundamental coordinate doesn’t exist, you can still identify a persistent individual in that it is the only one with nearly-identical memories to another one at the nearest location in the (indistinguishable-particle based) configuration space. (Barbour calls this the “Machian distinguished simplifier” or “fundamental distance”, and it matches our non-subjective measures of time.)
ETA: See Vladimir_M’s response below; I had misread his comment, thereby criticizing a position he didn’t take. I’ll leave the above unchanged because of its discussion of fundamental distance as a related metric.
You can quite clearly recognize that there is a being of approximately the same composition and configuration in the same location from one moment to the next.
That’s why I wrote that “the concept [of personal identity] is more or less coherent assuming the traditional biological constraints on human life.” It falls apart when we start considering various transhuman scenarios where our basic intuitions no longer hold, and various intuition pump arguments provide conflicting results.
Arguably, some of the standard arguments that come into play when we discuss these issues also have the effect that once they’ve been considered seriously, our basic intuitions about our normal biological existence also start to seem arbitrary, even though they’re clearly defined and a matter of universal consensus within the range of our normal everyday experiences.
Point taken, I misread you as saying that our intuitions were arbitrary specifically in the case of traditional biological life, not just when they try to generalize outside this “training set”. Sorry!
Evolution may have reasons for making us think this, but how would you get that the identification of an individual existing through time is subjective? You can quite clearly recognize that there is a being of approximately the same composition and configuration in the same location from one moment to the next.
Even (and especially) with the Mach/Barbour view that time as a fundamental coordinate doesn’t exist, you can still identify a persistent individual in that it is the only one with nearly-identical memories to another one at the nearest location in the (indistinguishable-particle based) configuration space. (Barbour calls this the “Machian distinguished simplifier” or “fundamental distance”, and it matches our non-subjective measures of time.)
ETA: See Vladimir_M’s response below; I had misread his comment, thereby criticizing a position he didn’t take. I’ll leave the above unchanged because of its discussion of fundamental distance as a related metric.
SilasBarta:
That’s why I wrote that “the concept [of personal identity] is more or less coherent assuming the traditional biological constraints on human life.” It falls apart when we start considering various transhuman scenarios where our basic intuitions no longer hold, and various intuition pump arguments provide conflicting results.
Arguably, some of the standard arguments that come into play when we discuss these issues also have the effect that once they’ve been considered seriously, our basic intuitions about our normal biological existence also start to seem arbitrary, even though they’re clearly defined and a matter of universal consensus within the range of our normal everyday experiences.
Point taken, I misread you as saying that our intuitions were arbitrary specifically in the case of traditional biological life, not just when they try to generalize outside this “training set”. Sorry!