I think most people would find it much more insulting to be refered to as "parasites" than as "little shits".

But the question of insult or "offense" is not really the point. In both cases what is involved is a kind of euphemism that seeks to distance us from what is involved. A fetus or embryo is not parasite, nor a bodily waste product, but a human being at an early stage of development.

I don't think talking about hypothetical cloning from single cells is really relevant here, Wolfgang. A single cell is not a human-being-at-an-early stage-of-development whether it is an egg, a sperm or a blood cell.

I think there is good research evidence indicating that a definition of humanity based on "onset of pain perception" would actually kick in before current viability.