This book helped to completely change my understanding of depression and psychology in general. The biological/evolutionary and social explanation Mr. Gilbert offers for depression is something I have encountered nowhere else, yet is so basic and elemental and makes complete sense. This book clarified and simplified what was for me a dark, scary, overwhelming mystery, and helped me to finally see depression for what it is. I understand now that I'm not randomly and unfortunately afflicted with a strange disease that I'm powerless to affect, but rather all people have the potential to enter a depressed state, and similarly all people, including me, have the potential to live in a state of vitality/normality (whatever the opposite of depression is). It's helped me to see what conditions provoke depression's onset - and importantly, why - and which help heal and restore oneself. What a stroke of luck to have come across this helpful book and this wonderful author.