Ok, I have heard a lot of things about when life begins from a spiritual context... Catholicism says the instant an egg is fertilized you have life... Others believe its the Crowning that the spirit enters the body... etc... but they all coincide with some physical event... so please... tell me what significance is 14 days? What event has taken place ?
Sounds to me like a simple cop out to let stem cell and other research go on without being burdened by that pesky morality thing.
tell me what significance is 14 days? What event has taken place ? I don't believe that any particular significance should be given to any particular number of hours following conception, since the position of the ovum within the fallopian tube or uterus when fertilization occurs can greatly affect the timetable and outcome of development.
That having been said, there are a number of landmarks which are IMHO as significant as fertilization in the human development process. For example, from what I understand implantation (or, to be more precise, the fairly rapid sequence of events surrounding implantation, collectively) marks the point at which:
- The number of individuals to be produced from the implanted embryo is established [if twinned embryos implant separately, the landmark would apply to them individually]
- The embryo passes the "point of no return", beyond which it must either grow or perish; before that point, an embryo's development could be suspended indefinitely by freezing in N2.
- The embryo reaches the stage where it can be expected to develop into the baby in the absense of any abnormality or complication.
- The interface between mother and embryo is established.
- Pregnancy becomes biologically detectable.
- The embryo has an available source of nutrients to begin work on producing the baby itself (as opposed to the scaffolding necessary to create it).
Although certain regulations should be put in place regarding lab experimentation on human embryos (an acorn which is hydroponically germinated would be considered a sapling rather than a seed, even if it was not planted), I think in general implantation is a better developmental landmark than fertilization.