ArmandoAlvarez wrote:

I heard a story on the radio about researchers who want to create chimeras of humans and non-human animals so that they could grow human organs (for transplantation) in, for example, sheep or pigs.  They started getting into the ethical debates about this, but it got me wondering:

Supposing someone did insert human genes into a (non-human) animal, or animal genes into a human, how would you know whether it had a rational soul or rights?  Presumably, inserting a single human gene into an animal doesn't necessarily give it a rational soul, or the E. coli that have been given human genes to produce insulin would have rational souls.  Similarly, inserting a single gene from a pig into a human wouldn't take away that person's rational soul.

If the scientist presents us with a human/pig chimera that has substantial genes from both species, how do we know whether it has a rational soul?  We can't just test its reasoning ability; some humans are incapable of reasoning yet have rational souls.  So how do we know?

(I guess the question would also apply if we met an alien species.)

Let's be explicit about a few necessary assumptions which enable the discussion in the first place.

- The soul enlivens the body in a real sense. The body cannot have life, biology and physiology without a soul.
- The soul integrates the mind and personality with the body.
- Animals have animal souls. Humans have human (rational) souls. These two are distinct and not interchangeable.

From the last point it follows that when human genes are injected into an animal or when human organs are transplanted to an animal, this does not make the animal a human. Rather, the animal soul absorbs the human organ/genes as per animal nature. This may occur with or without pathological complications, given some specifics such as compatibility of gene/blood types etc.

When the human organ has matured in an animal and gets transplanted to a human body who happens to need it, this should not make the human an animal. Rather, the human soul absorbs the organ to a degree of success. There may be lack of success, in which case complications follow, but these will be human pathologies, not animal pathologies.

Well, I'm not a vet, just guessing here.