Michael Gerson, a former presidential speechwriter, delivered a sermon at Washington National Cathedral in which he talked about being hospitalized for depression:

Like nearly one in 10 Americans — and like many of you — I live with this insidious, chronic disease. Depression is a malfunction in the instrument we use to determine reality. The brain experiences a chemical imbalance and wraps a narrative around it. So, the lack of serotonin, in the mind’s alchemy, becomes something like, “Everybody hates me.” Over time, despair can grow inside you like a tumor.

But then you reach your breaking point — and do not break. With patience and the right medicine, the fog in your brain begins to thin. … Over time, you begin to see hints and glimmers of a larger world outside the prison of your sadness.

I think this medical condition works as a metaphor for the human condition. All of us — whatever our natural serotonin level — look around us and see plenty of reason for doubt, anger and sadness. A child dies, a woman is abused, a schoolyard becomes a killing field, a typhoon sweeps away the innocent. If we knew or felt the whole of human suffering, we would drown in despair.

The answer to the temptation of nihilism is not an argument — though philosophy can clear away a lot of intellectual foolishness. It is the experience of transcendence we cannot explain, or explain away … there is this difference for a Christian believer: At the end of all our striving and longing we find, not a force, but a face. ... God’s promise is somewhat different: That even when strength fails, there is perseverance. And even when perseverance fails, there is hope. And even when hope fails, there is love. And love never fails.