When does life begin?

[Syne]

Proteins, organelles, and molecular building blocks are not, themselves, human life. And copies of parent DNA are not a new, unique DNA.

Didn't dance around anything. You asked, "If a woman froze several embryos, used one, and discarded the rest, would consider that murder?" I told you how it wouldn't be. You should have been able to suss out the rest for yourself. Many ethical women/couples willingly pay to keep frozen embryos stored indefinitely or try to donate them to infertile couples. And some even have them implanted when pregnancy is unlikely, so they die naturally, or even have all of them implanted at once, like Octomom. https://www.parenting.com/article/the-fa...en-embryos IOW, there are ethical options.

If you’re using the "unique genetic" argument then I think life begins at conception.

"The single-celled embryo is a very different kind of cell than that of sperm or oocyte, and contains a unique genome that will determine most future bodily features and functions of his or her lifetime.

It is clear that from the time of cell fusion, the embryo consists of elements (from both maternal and paternal origin) which function interdependently in a coordinated manner to carry on the function of the development of the human organism.  From this definition, the single-celled embryo is not just a cell, but an organism, a living being, a human being."

The American College of Pediatricians concurs with the body of scientific evidence that corroborates that a unique human life starts when the sperm and egg bind to each other in a process of fusion of their respective membranes and a single hybrid cell called a zygote, or one-cell embryo, is created.


https://www.acpeds.org/the-college-speak...ife-begins

I believe I've consistently said "unique DNA". A "unique genome" is just the "complete set of genes or genetic material present in a cell or organism". It doesn't differentiate between uncombined contributions and an organism's own unique DNA. Again, "a unique genome that will determine most future bodily features and functions" is only a potential human life. You're just grasping at straws to make the same argument you've already made...which is not defined by science as human life. Not even by this criteria of your cited source: "(2) an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent: a living being." They are stretching this dictionary definition of "organ", and while all cells are "living beings", no scientist would call a cell a human. At best, it is a proto-human, i.e. potential human.

And a medical source has external, practical considerations that pure biology does not, like the need to be conservative in light of the Hippocratic oath and inability to accurately assess the moment any given zygote becomes an embryo.

[Secular Sanity]

They are stretching this dictionary definition of "organ", and while all cells are "living beings", no scientist would call a cell a human.

But would they call two cells a human being?

And the morning after pill? Is it ethical?

[Syne]

They are stretching this dictionary definition of "organ", and while all cells are "living beings", no scientist would call a cell a human.

But would they call two cells a human being?

No.

[Image: 550px-HumanEmbryogenesis.svg.png]

And the morning after pill? Is it ethical?

Yes. It even takes about 24 hours for the sperm to fertilize the egg after sex.

[Secular Sanity]

But would they call two cells a human being?

No.

I'm lost again because you said just that mitosis is where you draw the line.

Is that where you draw the line in sand, cell division?

It's a definite line defined by science. Everything else is arbitrary.

I believe I've consistently said "unique DNA". A "unique genome" is just the "complete set of genes or genetic material present in a cell or organism". It doesn't differentiate between uncombined contributions and an organism's own unique DNA. Again, "a unique genome that will determine most future bodily features and functions" is only a potential human life. You're just grasping at straws to make the same argument you've already made...which is not defined by science as human life. Not even by this criteria of your cited source: "(2) an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent: a living being." They are stretching this dictionary definition of "organ", and while all cells are "living beings", no scientist would call a cell a human. At best, it is a proto-human, i.e. potential human.

At what phase exactly do you think it obtains its own unique DNA? When does it transform from a proto-human to a human?

[Syne]

But would they call two cells a human being?

No.

I'm lost again because you said just that mitosis is where you draw the line.

Where? O_o
I think you're imagining things, deary.

Is that where you draw the line in sand, cell division?

It's a definite line defined by science. Everything else is arbitrary.

Ah. Yes, you are lost. That reply was about BEFORE it was human life...you know, when it would be ethical to destroy a frozen embryo. You're conflating the answer to that with when it becomes a human life.

I believe I've consistently said "unique DNA". A "unique genome" is just the "complete set of genes or genetic material present in a cell or organism". It doesn't differentiate between uncombined contributions and an organism's own unique DNA. Again, "a unique genome that will determine most future bodily features and functions" is only a potential human life. You're just grasping at straws to make the same argument you've already made...which is not defined by science as human life. Not even by this criteria of your cited source: "(2) an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent: a living being." They are stretching this dictionary definition of "organ", and while all cells are "living beings", no scientist would call a cell a human. At best, it is a proto-human, i.e. potential human.

At what phase exactly do you think it obtains its own unique DNA? When does it transform from a proto-human to a human?

Since it's not a subjective opinion, you should be able to look that up for yourself.
Let's see if you can manage.

[Secular Sanity]

Most of them seem to agree with Yazata’s answer to—when does life begin, but they’re still divided on when a fetus become a person.
Some hold the fertilization view (zygote). Some have the implantation view, and some the gastrulation view. Then we have the neurological view, the viability view, etc.

But you believe that it obtains its own unique DNA when the single cell divides into two. Is this correct? And this is where you feel it’s unethical to destroy a proto-human. Is this correct?

When does it transform from a proto-human to a human?

Since it's not a subjective opinion, you should be able to look that up for yourself.  
Let's see if you can manage.

Hmm...if there's a scientific consensus or an objective answer to this one, I sure haven't seen it.

Do you have a link, book, lecture video, or anything else?

When exactly, do you feel that it transforms from a proto-human to a human?

[Yazata]

If this is going to be an abortion discussion, then we probably need to acknowledge that there's a sliding scale and that we are often using words imprecisely and talking about different things.

1. When did life begin? Some 4 billion years ago. It's existed continuously since then, generation to generation.

2. When did human life begin? Most biologists would probably classify what kind of life a living thing is by genetics. If some example of life possesses a human genome, then it's human. (More or less, since there are variations in the human line.) A severed finger, perhaps. So human life will have originated more than a million years ago if we are talking about pre-human hominins, or maybe only 150,000 years ago if we are talking about anatomically modern humans.

3. When does a particular human individual begin? We don't just want to know whether the severed finger is a human finger, we want to know whose finger it is. Again, I think that most biologists would address that genetically. A particular genetic conformation, still human but different from either of the parents, would seem to appear upon conception, when the chromosomes of the haploid sperm and egg merge to form a diploid individual.

4. When does a human organism begin? Hard to say, that's a matter of definition. Must a human organism bear anatomical resemblance to an adult organism? How much resemblance? Must it be capable of living independently, not supported by a placenta? Another question is when does a human organism end? A "brain-dead" individual is obviously still an anatomically-human organism. If its heart is still beating and its cells still metabolizing, it's still alive.

5. When does a human person begin? Sometime after birth, I guess. Newborn infants obviously aren't fully functioning adult humans. It's very difficult for us to put ourselves into their heads and to say to what extent they are self-aware persons at all. Infants and toddlers seem to grow into personhood over a period of time. What's more, our personalities, who we are in some important sense, is constantly changing as we experience life, live and learn. Am I the same person that I was when I was 20? This question is easier at the other end of life, since "brain death" refers to lack of brain function as indicated by measures like EEG, and biologists almost universally equate brain function with the ability to generate a personality. ("Brain death" is a bit of misnomer, since many of the cells of a "brain-dead" brain are still alive in the cell biology sense, even if the brain isn't functioning. Which raises the question of recovery from diagnoses of brain death.)

6. There's another thing to consider too, the human potentiality. Why do we think that it's wrong to murder somebody? Part of the answer seems to typically be that the murderer is taking away the victim's future. All the things the victim might do, all the experiences he or she might have, the loves, the interests... So when does that potentiality arise?

[Zinjanthropos]

YAZ...For this planet I agree 100% with point 1. The other points are regarding a life form (form of life if preferred)specifically human beings. For me life forms are always alive, there is no beginning of life for an individual and it's innate or natural for a life form to possess life. IMHO of course .

The question is this, is it OK to kill the life form of our own species before it exits the womb? Maybe that is what you refer to in Point 6. Philosophizing about such things may be tough, amoral, guilt ridden, or bring out the full extent of any number of undesirable emotions. How to not offend or display the willingness to be straightforward and blunt is perhaps the biggest conundrum facing an individual on this topic. Argument pro or con used to be the right of the unborn child versus the right of a mother to abort.... has that changed?

[Syne]

Most of them seem to agree with Yazata’s answer to—when does life begin, but they’re still divided on when a fetus become a person.
Some hold the fertilization view (zygote). Some have the implantation view, and some the gastrulation view. Then we have the neurological view, the viability view, etc.

No credible science source views viability as a definition of human life. And you'd have to cite some sources on the others.

But you believe that it obtains its own unique DNA when the single cell divides into two. Is this correct? And this is where you feel it’s unethical to destroy a proto-human. Is this correct?

No.

Following that first division, some genes from the new genome are accessed to make proteins, but maternal transcripts still dominate development.

5. Cleavage. Divisions ensue. The cells of an 8-celled embryo (day 3) have not yet committed to becoming part of the embryo “proper” (one with layers) or the supportive membranes. Such a cell can still, on its own, develop. An 8-celled embryo whose cells are teased apart could lead to an octamom situation.

6. Day 5. The new genome takes over as maternal transcripts are depleted.
- https://blogs.plos.org/dnascience/2013/1...imepoints/

Maternal genes still directing most development would be an argument for "part of the woman's body". So somewhere between day 3 and 5 it actually becomes a unique organism, developing under its own DNA plan.

When exactly, do you feel that it transforms from a proto-human to a human?

Again, there's no feeling or opinion about it. It's when its development is largely directed by its own unique DNA.

[Zinjanthropos]

According to this guy, life has been around since practically the beginning. 

https://www.extremetech.com/extreme/1761...-years-ago