If Adam survived as both twins, there would be one human being living two distinct individual lives, which is impossible since the twins are clearly two separate human beings.

References to identity in this debate come from objectors to this argument, who apply the argument from fission to a real life version of it, namely, twinning. An embryo might split any time generally before the two-week point in fetal development, and those two embryos could develop into fully formed infant twins. The question for the advocate of the above argument to consider is, in such a case, what happens to the original human being, the embryo we will call Adam? There are only three possib