"The opposite of depression is not happiness, but vitality, and it was vitality that seemed to seep away from me in that moment." In a talk equal parts eloquent and devastating, writer Andrew Solomon takes you to the darkest corners of his mind during the years he battled depression. That led him to an eye-opening journey across the world to interview others with depression -- only to discover that, to his surprise, the more he talked, the more people wanted to tell their own stories.