People seem very arrogant when they say 'I'm right and you're wrong', but in practice we all believe we're right. We have a staggering arrogance in our own belief. That can be tempered by not being 100% certain; by being provisional. No matter what the debate is, very few people have the modesty to suspend judgement on a whole range of things; most intelligent people have an opinion and are expected to have an opinion by other people - but it always requires making a personal judgement that goes way-beyond your expertise. We do it all the time.