The potential of the human embryo.

A higher order potential analysis of moral status clarifies the issues that divide Human Being Theorists who oppose embryo research from Person Theorists who favor embryo research. Higher order potential personhood is transitive if it is active, identity preserving and morally relevant. If the transition from the Second Order Potential of the embryo to the First Order Potential of an infant is transitive, opponents of embryo research make a powerful case for the moral status of the embryo. If it is intransitive, then the Person Theorist can draw lines between levels of moral status that permit embryo research to proceed.