Mikah wrote:
I will ignore for now the strict definition of parasite. Being bodily dependent on your mother is a part of the human life cycle, usually extending beyond birth in the form of breastfeeding. Prematurely severing that dependence and seeing if the baby can survive is not a satisfactory definition of the beginning of human life. It's saying "if I do this and you survive you were alive all along, if I do this and you die, you were never really alive." If you never did this thing in the first place, it wouldn't even be an issue and from there how would you go about defining the beginning of life?
As an aside, are parasites really alive? If you remove one, and it cannot live independently of you and it dies, was it never really alive? Being able to survive independently of the body of another life form, same species or not, doesn't seem to be a rigid or sensible starting point for defining life in general, let alone where it begins.
You also imply that bodily dependence is so very much different from any other kind of dependence. I'm not saying it's exactly the same but I struggle to view it as a sacrosanct. If you were to try to define the beginning human life as a more general independence from other humans, no one would ever really be alive.
Just to point out the argument you present would seem to be inconsistent with your earlier argument,
Mikah wrote:
I was careful with how I worded it. A sperm or an egg alone cannot be or become an individual human being
This would indeed apply to a fertilized egg. It is fully dependent upon another distinct organism for its survival, but even more so, it is fully dependent upon that organism to develop from a single celled egg (which is not a human being yet) to something that all of us can agree is a human being (say, some point where it is viable).
Also, parasites are indeed considered alive. It might help to remind you that any animal which eats another organism is also dependent upon another organism's body for survival. Parasites have simply found an exceedingly lazy way to go about it.
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