^really, you are saying your parents have had no influence on who you? Not in any way what so ever? We might not always want to admit it but our parents can play a part in who we become.
But Tuvok and Neelix are not his parents, we give our children life but they do not take our life in exchange. Tuvix has taken both of them hostage.
In order to take someone hostage (or commit a crime in any way) one must be able to consciously act. Tuvix could not consciously act to create his own life. There is not hostage-taking.
There are species that die after reproduction. Just because that isn't true of humans, doesn't mean it isn't true.
IDIC. Remember that?
In multiple episodes of Star Trek, in all of the series, it's been made clear that all sentient life has the right to exist.But under Federation LAW, Tuvix would be a unique indivdiual and be entitled to all the rights that the Federation bestows.
This one is only your assumption of Federation Law, in reality in the US a person cannot be forced to give up any part of their body for another, even after the donor has been declared legally dead. There has to be permission, either by the donor himself before his death, or by the next of kin afterward.
Your citation of transplant law actually works against you (not surprising, because you've never studied medical ethics, which has been made apparent by your posts in this thread).
No, organs cannot be donated without consent. While we might frown upon a child who is unwilling to give a parent a slice of her liver, we cannot compel her to risk her life to save another.
Tuvix was created by a process called symbiogenesis. Neelix and Tuvok are his parents. He cannot be compelled to give up his own life to save that of his parents.
Which is why the Doctor said, "No."
Another factor to consider is that the EMH would be controlled by ethical subrouties, rather than emotion. And yes I know when he had only time to save one person with both patients having an equal chance to survive. Shame they didn't put one into stasis r even transporter stasis so they could save both. But that wouldmean using continuity.