All life comes from life, I am part of the chain even now as you are also, but that is not the point, is it?
No, because when life begins isn't the issue. What we should be asking is when personhood begins (or something very similar).
A human being that does not have sentience does not have the right to life by that criterion. Are you sentient when under the effects of anesthesia? Or when in a coma? Are you still human during this period?
I would still be human if I was brain-dead and being kept alive by machines. I would still be human - and alive, discrete and unique - if all that was left of me were cells growing in a petri dish. But I would not exist as a person. While under anaesthetic or in a coma, my personhood might be temporarily suspended but it's still there. How about we extend rights to beings that have been sentient in the past and are likely to be sentient again in the future even if they are not currently so? That seems reasonable to me, in a way that extending rights to entities that may at some future point achieve sentience does not.
It must be treated as innate, inalienable and intrinsic to human life.
That's not what I asked. I asked from where it derives. Your answer that it must be treated as innate merely tells me that your preferred end requires such treatment. Why must it be treated this way? What happens if we treat it differently?
It cannot be treated as something granted from without by any human authority. Who decides which characteristics make one a human? And to what degree must these characteristics be present? Ultimately, these decisions will be made by those in power. This the foundation for totalitarianism.
I don't see how. You are the one who seems to be making a totalitarian judgement. I welcome the questions you ask. When exactly should a being be granted rights, and what rights should those be? Merely declaring that being a member of H. sapiens gives an entity "innate, inalienable and intrinsic" rights adds nothing to the argument.
We are moving on that path, as this recent article in he Telegraph illustrates.
British ethicist: Senile should be “put down”
I welcome such a move, not forcing people to be "put down" but allowing people to painlessly opt out of life when that life is no longer worth living. I don't know a single person who would rather be a drooling, incontinent shell unable to recognise the family they burden than to be allowed to die with dignity, and nor, I suspect, do you.
Human embryos, like fully mature human beings, are whole human organisms.
As such, they are living members of the species homo sapiens.
Human embryos contain the epigenetic primordia for internally directed maturation as distinct and complete human individuals.
They are human.
Agreed, but you keep just saying the same thing in different ways. Yes, it's human, but why is that the important criterion? Replace the word "human" with "bonobo" and "Homo sapiens" with "Pan paniscus" in your statements above, and nothing significant changes. Add a chromosomal abnormality to the human zygote and any arguments you have about their relative potential future intelligence become worthless.
Assuming the nonexistence of spirituality or other dualisms:
1) You and I are essentially physical organisms;
2) we came to be when the physical organisms we are came to be; and
3) the physical organisms you and I are came to be at conception.
4) You and I once were human embryos
I initially thought the above was just a rehash of the trivial point you'd already made several times (namely, that a human embryo is human). But it's slightly more. You're saying that you began to be you and I began to be me at conception. That may be true in some sense. But there are many ways in which it is not true. The person I am certainly didn't just pop into existence fully formed. It has developed over the last 32 years or so, and while it's difficult to say exactly when I became a person capable of feeling, of suffering, of loving, of hoping and dreaming, it is certain that none of those things happened at conception. I'm glad the embryo that became me wasn't aborted, but I'm just as glad that the sperm that became half of me wasn't wasted in a wank so that doesn't really add to the argument.
Can you give me a good reason why we should treat a zygote like a person? I haven't seen one in your posts so far.