I have previously explained two good arguments for the pro-life position, the Substance View and the Future of Value arguments. I would like to share with you a third.
It’s an argument that Alexander Pruss has termed an identity-based argument. Stephen Napier defends a similar argument which he has termed the Unity argument, but my exposition of this argument will follow Pruss’ essay I Was Once a Fetus: An Identity-Based Argument Against Abortion, with additional notes by Napier where appropriate. I will merely be giving a basic exposition of the argument; I would recommend reading the essay for a more robust defense, as well as answering potential objections to the argument.