I don't know the context in which Jonathan Swift said "comparisons are odious", but it was some time ago. Recently, the British clinical psychologist Oliver James said that "destructive, depressive comparing is the great curse of our time".
But whether comparisons are odious or destructive in one sense is irrelevant - they are what human beings do. All the time. In fact, it's by making comparisons with others that we get our sense of who we are, of who we might like to be like - or not like.
So it's easy for those who want to rubbish Assessment is for Learning to claim it's about not sharing grades or levels of marks with pupils in case they compare themselves with each other and become demotivated. Out in the real world, they say, youngsters will get compared with other people all the time.
It has been said that "happy ever after" only happens in fairy stories. And various thinkers have believed that recognising that life is psychologically hard is the first step towards being truly happy. If we expect life to be difficult, then it's much easier to react to the range of inevitable setbacks, large and small that we face along the way. Children will not cope if they are over-protected.
So why the issue about sharing grades and levels? Pupils certainly need to know where they stand: the question is whether they need to know where they stand all the time - especially when, as Alan McLean puts it, fear of failure in public is probably the biggest inhibitor of motivation to learn in the classroom.
Indeed, this is an aspect of what Mr James is talking about: "destructive, depressive comparing" is a symptom of what he calls "affluenza". This is our obsession with comparing ourselves to people who have more money than us, are smarter than us, have smarter children, send them to better schools, get better grades and so on.
It's in the context of a society with affluenza that constant comparisons are odious. But this is not an argument for getting rid of them. It is an argument for helping young people to develop the mindsets or the attitudes they need to cope with comparisons.
Thankfully, we have well over 10 years of work from modern psychology on these mindsets to draw upon. Martin Seligman and Carol Dweck, leaders in the field, both fervently believe that optimism can be learnt and positive mindsets can be taught, but are more convincing about what we should not do rather than what we should do. The idea that we can artificially boost self-esteem has been discredited. The credibility of teaching emotional intelligence is under question.
Assessment is for Learning still provides the most practical help to teachers to help young people develop positive mindsets. It's not primarily about comparing yourself against others, but comparing yourself against your previous best - then discussing what did or did not work for you and how you can do better. It's as simple and as complex as that.
Ian Smith is founder of Learning Unlimited.