QUOTE(phaedrus @ Oct 15 2003 @ 02:30 PM)
Just 3 hours after fertilization the zygote starts to divide cells. By every definition of known science it is alive, and human, at this point. It makes its way down the fallopian tube and develpes into an embryo in about a week. Once the fetus is implanted the female body protects protects it from menstruation by secreting a hormone. The primordial embryo begins to form organs in a process called morphogenesis and all the vital parts for a human being are evident. By the end of the sixth week are forming and at this point its only about 1/2 of an inch long.
Everything that defines a human being is evident within weeks. I'm not sure where I would place to point where the fetus becomes a child but there is no reason to conclude that this is not a person after the first trimester.
By every definition of known science, all cells are alive including individual gametes, the product of another cell division known as meiosis. When you say everything that defines a human being is evident within weeks, what specifically do you consider to define a human
being? Excluding the capacity for consciousness for a moment, a fetus still lacks the lung and neurological development to survive as a separate entity until at least
(usually after) the 20
th week of gestation.
QUOTE
It is not only viable at the 12th week it has every vital function by which we define personhood. I'm going to try to be clear at this point, once every vital function is intact it is a person. This whole process involves no more then 12 weeks in my estimation. It must be considered conscious when the brain starts functioning, I think that this is done well within the 12 weeks of the first trimester.
What might those vital functions be that
you use to define personhood. Clearly it lacks the functions
I hold to define personhood, so I'm not sure what your definitions might be. There is some electrical activity in the brain prior to the 20
th week, but there is no large-scale linking of neurons until approximately the 24
th week of gestation or later. Science has been able to monitor and establish the necessary brain waves for human thought and it is not present until well after the 12
th week
(between 24 and 30).
QUOTE(PrismPaul @ Oct 15 2003 @ 02:36 PM)
I still think your viability component is very problematic. You define it as:
QUOTE
the ability to sustain life independent of another particular person's continued biological function
It seems like the word "biological" is key in your definition, but it still strikes me as a strangely arbitrary distinction. Dependence is dependence, whether one is dependent on the biological function of a caretaker or, as is the case with a 1 year old child, dependent on the fact that a caretaker feeds you. In both cases, the subject is completely dependent on the caretaker for survival. Can you expound on why "biological function" is significant to you?
Actually, key to my definition is another
particular person's continued
biological function. This is important to me because prior to this, while it is clearly a separate form of life, it is no more an individual entity than any other cell or group of tissues present in a woman's body. If the woman dies prior to this viability then the zygote, embryo or fetus dies just as the other cells and tissues in her body do.
QUOTE
You are a person not because you are currently conscious, but because you will be conscious in the morning. Just as a fetus will be conscious in a matter of weeks. What is the purpose of the word "capacity"? You need it because it is different to have "X" than to have the "capacity for X". Isn't the difference just a matter of timing?
I emphasize the capacity because early in gestation the zygote, embryo or fetus lacks any capacity to think without the linking of neurons necessary for such. Whether I am awake or asleep
(including the comatose), I retain the capacity for consciousness.
As for timing:
QUOTE
Well, of course, a fetus that does not yet have the capacity for consciousness, will have that capacity in time as well.
As the term fetus can be applied for over 20 weeks of a
(traditionally) 36 week gestation period, there is certainly no guarantee that any fetus
will have such a capacity in time. As I have stated previously elsewhere on the site, it is estimated that some 80% of all fertilized eggs will spontaneously terminate, whether they do so prior to or upon consideration as a fetus. Prior to viability with the capacity -- or at least the ability to develop the capacity outside the womb -- a fetus has only an unknown potential to develop such a capacity.