‘What is well-being?’ – a hard question. One thing that we need to understand first when we ask this question is that well-being is not a purely scientific or technical term; it’s rather value-laden. When we talk about well-being, we say “this is what makes someone’s life go well” or “this is improving their well-being”, “this is good for them”. Whenever you hear a phrase like that, “good for someone” or “bad for someone”, you have to recognise immediately that there is a value judgement involved. So, this is not something that we can answer with controlled experiments. We have to define well-being in terms of what we care about. Because of this nature of the concept of well-being, there’s been a lot of debate over the centuries and, in particular, in recent decades between people coming from different disciplines and different perspectives about what well-being is. In this context, it’s useful to do a bit of a historical analysis of what kind of ideas have been popular in the past and what sort of debates have characterised the history of thinking about well-being.