I am not the zygote I came from because a different human could have come from it

Abstract

I argue that a human zygote which naturally develops into an infant (or adult) without twinning could have naturally developed into a numerically different infant without twinning. The cells of an early human embryo differentiate into two distinct types, namely, the inner cell mass, from which (almost) all the cells of the infant at the time of birth originate, and the trophoblast, which produces no tissues of the infant but only part of the placenta. I argue that the cells which actually yield the trophoblast could have formed the inner cell mass and naturally developed without twinning into an infant, who is numerically distinct from the infant actually coming from the zygote.

From this, I derive the conclusion that a zygote is not identical with the infant it develops into. This implies that a zygote does not have a “future like ours”' and strongly suggests that it is not a human.