Andrew Brown’s account of a conference/debate on embryo research is worth reading, but too long to quote in its entirety. Herewith the beginning and end; follow the link and read the whole thing.
Andrew Brown: What is it that makes an embryo human, and when?
I don’t know any field of argument where the line between Christian and secular reasoning is so sharp as in embryo research. What I mean here is that the scientist proceeds from what can be done to reasoning about the nature of the things it can be done to: the Christian starts with an intuition about the nature of the subject, and then decides what may be done to it.
At a conference yesterday organised by the Progress Educational Trust, representatives of different faith traditions — and the secular philosopher John Harris — gave their views on what it is permissible to do with human embryos. The sharpest, and so the most valuable arguments came between Harris and the representatives of Catholic orthodoxy, whose champion on the panel (there were others in the audience) was Professor David Jones, of St Mary’s College, Twickenham.
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This is where the God of orthodox Christianity comes in handy, because he is by definition the only being who can value everything entirely for its own sake. Everything else in the universe — possibly everything in the universe — finds other things valuable and worthwhile in as much as they serve its purposes. Certainly there is nothing and no one is supremely valuable to all human beings. No Martian anthropologist would conclude that our species thinks that other people’s babies have much value.So why do we think that they ought to?