"If we also consider only the present moment is real, then past X and future X don't exist. Since it is impossible that the same person exists and does not exist, we conclude present X and past X are different persons."
I cannot agree with your logic here, you have stated past X does not exist, then in the next sentence you say it is a different person than present X (implying that it does exist and can be compared and contrasted). I don't belive that there is a meaningful conclusion to be had by comparing something real (present X) to something nonexistent (past X) in any case.
This is my first time reading the Stanford's argument against presentism, and possibly I am not understanding this fully but point (6) "Socrates exists", is either obviously true (Socrates was a man, man exists, so Socrates exists) or obviously false (he is long dead, so he does not exist). Maybe this is because the logic mixes up past and present. If we logically arrive at "(6) Socrates exists", then we should be able to use present tense and have the same logical validity, point (2) becoming "Socrates IS wise", which is false, as a dead person cannot be wise.
I am unsure on whether or not presentism is true or not (personally I do not care, I don't see how it would make a difference to me either way). Possibly time exists and we can navigate through it (either by the "regular" passage of time, maybe time travel is possible in the forward or backward direction), or time exists "all at once", and we living human beings are somehow limited to only experience it instant by instant. Or else time does not exist at all or is essentially meaningless (or is a human construct, in the same way that numbers and math are).
"If we also consider only the present moment is real, then past X and future X don't exist. Since it is impossible that the same person exists and does not exist, we conclude present X and past X are different persons."
I cannot agree with your logic here, you have stated past X does not exist, then in the next sentence you say it is a different person than present X (implying that it does exist and can be compared and contrasted). I don't belive that there is a meaningful conclusion to be had by comparing something real (present X) to something nonexistent (past X) in any case.
This is my first time reading the Stanford's argument against presentism, and possibly I am not understanding this fully but point (6) "Socrates exists", is either obviously true (Socrates was a man, man exists, so Socrates exists) or obviously false (he is long dead, so he does not exist). Maybe this is because the logic mixes up past and present. If we logically arrive at "(6) Socrates exists", then we should be able to use present tense and have the same logical validity, point (2) becoming "Socrates IS wise", which is false, as a dead person cannot be wise.
I am unsure on whether or not presentism is true or not (personally I do not care, I don't see how it would make a difference to me either way). Possibly time exists and we can navigate through it (either by the "regular" passage of time, maybe time travel is possible in the forward or backward direction), or time exists "all at once", and we living human beings are somehow limited to only experience it instant by instant. Or else time does not exist at all or is essentially meaningless (or is a human construct, in the same way that numbers and math are).