ROME, Stem cell research using material taken from human embryos continues to be hotly debated. Advocates of using embryos maintain that at such early stages, the cells cannot be considered a human person. However, a recent book by two philosophers argues the contrary.
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In "Embryo: A Defense of Human Life" (Doubleday), they maintain that the status of a human being commences at the moment of conception.
The book starts by recounting the history of a boy named Noah, born in January 2007. He was rescued, along with other frozen embryos, from the disaster that struck New Orleans in 2005. It was Noah's life -- a human life -- that was saved, George and Tollefsen point out, the same life that was later implanted in a womb and was subsequently born.
A human embryo, they continue, is a living member of the human species even at the earliest stage of development. It is not some type of other animal organism, or some kind of a clump of cells that later undergoes a radical transformation. Barring some kind of tragic accident, a being in the embryonic stage will proceed to the fetal stage and continue to progress in this development.
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http://www.zenit.org/article-22280?l=english