Feelings of numbness, powerlessness, and hopelessness are now so common as to verge on being considered normal. But what we are seeing is far less likely an actual increase in a disease of the brain than a series of circumstances that is drawing out a similar neurochemical mix. This poses a diagnostic conundrum. Millions of people exhibiting signs of depression now have to discern ennui from temporary grieving from a medical condition. Those at home Googling symptoms need to know when to seek medical care, and when it’s safe to simply try baking more bread. Clinicians, meanwhile, need to decide how best to treat people with new or worsening symptoms: to diagnose millions of people with depression, or to more aggressively treat the social circumstances at the core of so much suffering.

—James Hamblin, in “Is Everyone Depressed?”