And that's why it's best to avoid using words and turns of phrase that are liable to switch off the other parties listening chip - or which seem to be an attempt to beg the question.

One deeper assumption which I think all of us would agree about is thta killing fellow human beings is a bad thing to do - and then we'd divide about what kind of circumstances might justify doing somnething like that; and also probably about what we mean by "human being".

And there'd be other deeper assumptions about freedom, and disagreements about the limits on freedom. And about the role of law in society. And so on.