For the Stoics, the realisation that we can often choose not to be distressed by events, even if we can't choose events themselves, is the foundation… - Oliver Burkeman

Perfectionism is the voice of the oppressor, the enemy of the people,' the infinitely more sensible essayist Anne Lamott observes in her book on writing, Bird by Bird. 'It will keep you cramped and insane your whole life … perfectionism is based on the obsessive belief that if you run carefully enough, hitting each stepping stone just right, you won't have to die. The truth is that you will die anyway and that a lot of people who aren't even looking at their feet are going to do a whole lot better than you, and have a lot more fun while they're doing it.

And here lies the essential difference between Stoicism and the modern-day 'cult of optimism.' For the Stoics, the ideal state of mind was tranquility, not the excitable cheer that positive thinkers usually seem to mean when they use the word, 'happiness.' And tranquility was to be achieved not by strenuously chasing after enjoyable experiences, but by cultivating a kind of calm indifference towards one's circumstances.

Or consider the fraught topic of self-esteem. We tend to assume that having high self-esteem is a good thing, but some psychologists have long suspected that there might be something wrong with the whole notion – because it rests on the assumption of a unitary, easily identifiable self. Setting out to give your 'self' one universal positive rating may in fact be deeply perilous. The problem lies in the fact that you're getting into the self-rating game at all; implicitly, you're assuming that you are a single self that can be given a universal grade. When you rate your self highly, you actually create the possibility of rating your self poorly; you are reinforcing the notion that your self is something that can be 'good' or 'bad' in the first place. And this will always be a preposterous overgeneralisation. You have strengths and weaknesses; you behave in good ways and bad ways. Smothering all these nuances with a blanket notion of self-esteem is a recipe for misery. Inculcate high self-esteem in your children, claims Paul Hauck, a psychologist opposed to the concept of self-esteem, and you will be 'teaching them arrogance, conceit and superiority' – or alternatively, when their high self-esteem falters, 'guilt, depression, [and] feelings of inferiority and insecurity' instead. Better to drop the generalisations. Rate your individual acts as good or bad, if you like. Seek to perform as many good ones, and as few bad ones, as possible. But leave your self out of it.