Why do you think abortion is bad?
If
1) we agree that murding people is bad
2) at age 20 a human is a human with all the moral weight we give people
3) one day earlier he was also a human
4) we accept induction
5) we don't consider Ship of Theseus to be a debilitating objection http://en.wikipedia.org/wiki/Ship_of_Theseus
then the only Schelling point where non-human matter turns into a human is at the point of conception.
Thus I defend the right of every human being not to be murdered with medical instruments or poisons.
1) we agree that murding people is bad
2) at age 20 a human is a human with all the moral weight we give people
3) one day earlier he was also a human
4) we accept induction
5) we don't consider Ship of Theseus to be a debilitating objection http://en.wikipedia.org/wiki/Ship_of_Theseus
then the only Schelling point where non-human matter turns into a human is at the point of conception.
Thus I defend the right of every human being not to be murdered with medical instruments or poisons.