Which leads one to wonder how, exactly, the definition ever came to be in the legal dictionary. I understand what you were getting at, but at this point, all the philosophical wrangling has been long done. The rules of the game in the US were established with the writing of the constitution. Arguing over whether the definition of person in a legal dictionary is correct is as pointless an exercise as if a lawyer beleived that he could make his client's case work if he could just get the judge to accept a different definition of bankruptcy or void, or guilty for that matter.
In many cases, centuries of philosophical, and legal wrangling have gone before the defintion that one finds in the legal dictionary. At this point, however, all the wrangling in the world between you and me, or legal council and a supreme court justice is not going to change what it says.
If an entirely unconstitional decision had not been made and actual lives were not being lost in the thousands per day, a philosophical argument on the subject "just for fun" might be appropriate but at this point, such mental masturbation amounts to fiddling while rome burns. Abortion is serious business to me.
If you would like to engage in a philosophical sparing match on some topic in which lives are not on the line, I might enjoy the exercise, but not this topic. It simply isn't appropriate.