I think one of the reasons inflexible barriers exist on this issue is that life is viewed (here in the West) on a linear timeline; it has a definitive beginning, and it has a definitive end.Most of us are comfortable with the notion that death (lack of breath or heartbeat) is the end of that timeline. But the beginning is not so easily defined, especially with advances in modern medicine revealing much about development in utero. Because of our desire to 'cap' or quantify the notion of a human life, we want to ferment another moment that signifies the beginning as well.So, I believe that it is this notion of a fixed linear view of life that is the heart of this controversy. Which in some ways is ironic because religious people, those who have a firm belief in life continuing after death, seem the most insistent that there needs to be a clear starting point for it.
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