None of this really matters. The instant you can take a piece of it's DNA and identify it as a genetically unique Homo sapiens sapiens, then you've got yourself a genetically unique human. It doesn't matter what the cell ends up doing.
You have unique genetic material, but not necessarily a human being. To illustrate the point your fingernail clippings, beard shavings, and snot have your unique DNA but no one considers any of
that to be a human.
The question is whether or not it's a
being. Philosophically you could argue it both ways in that it is actually there (as opposed to in idea), but that it lacks some essential characteristics. This is probably why the fetus is often considered the start of human being-ness.[/QUOTE]
That's what I was getting at. Every distinct thing has necessary conditions to be considered a member of that set of things. Human beings have organs, structures, special tissues...these things don't exist in the embryonic stage. It's material that's ready to become a human being but hasn't at that point. Human gestation is a time dependent process. If it wasn't, it wouldn't take nine months to get a baby (slightly less to get a viable baby)
Could it be programmed to become an alligator's liver?
It could only be programmed to use the information contained in the original two cells, but those cells could be programmed to being any organ in the human body.
Some people clearly believe that something is a
human being if it is genetically unique from its parents, and it actually exists. Others think it needs to have at least some of the major structures in place. Others thing it's when the it can feel pain, and still other think it's not a human being until it's born alive -- there are lots of markers that people argue.
Of course it's debatable. It's been debatable for eons. [/QUOTE]
Alex, I was referring to human embryonic development. It is a well documented process. Everyone can watch the sperm and egg combine and divide until it eventually becomes a human being but the defining characteristics of a human being don't exist in the beginning stages until after development has taken its course.