Luisa Dillner: Seasonal affective disorder is a type of depression that comes on in autumn and lifts in spring. So how can you tell whether you have it?
Pete Cashmore: In the face of a Tory call for cuts to benefits for those who go without treatment, it is important to know how brutal some methods can be and why refusing them can be valid
Richard Layard and David M Clark's polemic about mental illness is a revelation – but they're a little too sure they have all the answers, writes Ian Birrell