Stem cell-research is a useful example of the clash between the absolute moral pronouncements of theism and a more rational morality based on objective facts.
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Yes, we believe that the soul is directly created and infused by God in the very moment of conception. It's not about the embryo having a neural system or not or ability to feel pain. It's about the soul already created - John_Mann
Catholics want to prohibit important medical research on the basis of the specific belief that god infuses the fertilised egg with a unique human soul at the moment of conception.
Objective facts show that this belief is impossible. These facts should give pause to those who would deny important medical knowledge to people suffering from debilitating diseases. It won't give them pause of course because their morality is based on the premise of "god says.... the end".