Julian Baggini

Trade has played a vital role in the social evolution of humankind. It allowed people to specialise, which raises both skill levels and efficiency. It brought people from different lands together, co-operating rather than competing over resources.

Metaphorical tone deafness is when people are unable to discern what is of value in something. I think I'm tone deaf to poetry, for instance. Despite having studied it into a second year of university, most of it just leaves me cold.

If I hammer my own thumb while doing some DIY, it's not nice, but it's not the end of the world. To care obsessively about similar levels of discomfort in animals seems to be a case of mistaken moral priorities.