another average american wrote:
We get back to where life begins, which I have said from the beginning is an unanswerable question, morally and scientifically.
Are you sure? In at least one scientific sense, logic, it can be narrowed down.
Take an adult human and work backwards. This person is fully grown, financially independent, and has offspring. A living human being? Of course.
Back up a decade and that person was an 18 year old teenager fully grown, fully capable of offspring but dependent on parents. Any less of a living human because it can not feel secure?
Back up another decade and that 8 year old person is a preadolescent, not capable of producing offspring but can rummage through to survive on its own - but poorly. Any less of a living human because it can not procreate?
Back up a few years more and that 2 year old person is a toddler and can communicate a little but is completely dependent on parents for shelter and food. Any less of a living human because it can not shelter itself or find food?
Back up to when the person is one week old and relies on breast milk from it mother for all it nutrients. Any less of a living human because it can't digest normal food?
Keep backing up to when the person is a baby just before the umbilical cord is severed. The person is crying (breathing) but getting all other nutrients from it's mother. Any less of a living human because it gets nutrients though the umbilical cord rather than a nipple?
Back up to when the person is a fetus just before delivery. The person is much like just after delivery, but relies on the mother for oxygen. Any less of a living human it gets oxygen through the mother?
Back up a few months to just before the fetus's nervous system can sense pain. Any less of a living human because some neurons aren't fully developed?
Back up to just before the heart begins to beat. Any less of a living human because it relies on the mother's blood pressure to circulate nutrients?
And on and on.
All of these are notable and significant stages of life but none have any more stake on defining the start of life than another. So with respect to identifying the placement of a time that an organism becomes alive, how can any of these be chosen? We can not.
We have to back up all the way to point that the organism started down that long path. At the point that from then on, stopping it requires intervention. That is the answer to when a human life begins.
This is only one part of many of this issue and therefore should not be the defining basis for policy, but if the question of when a life begins, there is an answer.