It’s true that most libertarians support stem-cell research that destroys early embryos, and also true, I suppose, that most of that majority of libertarians believes that this position follows naturally from libertarian principles. The same propositions are true of the “pro-choice” position on abortion. But I do not think it is true that one has to approve of the legality of abortion or of such research to be a consistent libertarian. (Some self-described libertarians agree with me.) If the libertarian proposition is, in a nutshell, “government exists to protect people against force and fraud,” then the question, with regard to these issues, is whether the embryo or fetus counts as a person. The libertarian proposition mentioned above does not itself furnish the premises to answer that question.