"Depression, in most of its manifestations, is the healthy suspicion that 1) there may not be an aim or point to existence, and/or 2) that the life people have actually created, the 'structure of society,' is not one worth participating in. The objective should not be to kill this suspicion, but to tame it and work with it."From a short essay by someone named Tim Ruggiero. Arthur Schopenhauer and R D Laing are both mentioned. I don't know if
R D Laing is still in print. If not, he should be. I don't have time right now to check. I can recommend Schopenhauer's Essays and Aphorisms (Penguin, just under a tenner).