It is a conundrum that has puzzled mankind since at least Plato and Aristotle.
Why do so many creative people throughout history — so many great artists and geniuses such as Robin Williams — seem to be touched by what the ancient Greek thinkers called "divine madness"?
And which came first for those graced by this "gift from the gods" — the genius or the madness?
Twenty-four centuries later, we are still puzzling, reminded once again of the seeming link between creativity and mental illnesses by the shocking suicide of Williams this week in his California home. He was 63, had long battled substance abuse and had recently sought treatment for depression.
Instantly, we recalled other artists who followed the same tragic path, a lengthy list that includes painters, poets, writers, musicians and designers: Vincent van Gogh, Ernest Hemingway, Virginia Woolf, Sylvia Plath, Kurt Cobain, Alexander McQueen to name just a few of the famous creatives who suffered from depression and committed suicide.
But is there a proven link between creativity and mental illness (which, strictly speaking, is not the same as being mad)? This is still a matter of hot debate.
A leading researcher in this field is Kay Redfield Jamison, a professor at Johns Hopkins University School of Medicine (who herself has bipolar disorder) whose studies seem to back up the popular idea of the "tortured genius." When, for example, she examined nearly 50 writers and artists in Britain, she found that more than 38% had been treated for a mood disorder.
On the other hand, some experts find this discussion absurd, such as psychologist Judith Schlesinger, author of 2012's The Insanity Hoax: Exposing the Myth of the Mad Genius.
She blames "misinterpretation" of what Plato meant, plus the fact that no one even agrees on what constitutes creativity or madness.
"There is no evidence...that a poet or comedian is any more disturbed than the mail carrier," she says. "People (are) asserting creative people (are) more prone to mental illness without a shred of proof. But the myth is so beloved and so ancient that people figure it must be true and there must be evidence."
Still, it's hard to argue with people's instincts.
"I don't think a couple of thousand years of human observation that there's something going on, is off," says Constance Scharff, director of addiction research at Cliffside Malibu, the celebrity rehab center in California that treats patients with addiction and psychiatric issues. "It's only in the last 10 years that we've had the scientific knowledge to prove the link, through neuroscience and brain imaging, but there's no doubt there's a connection."
But its exact nature is still unclear. Science and medicine are only now beginning to study what's going on — chemical, neurological, organic — in the brain, and also deal with the old and vexing problem of a cure: How to treat creatives successfully in a way that does not rob them of their creativity?
Call it the Hemingway problem: "They think, 'If I stop drinking I won't be able to write,' " says Scharff.
Psychotherapist Deb Serani, author of Living With Depression (and who nearly killed herself while in a depressed state at age 19), says people with bipolar disorders find ways to cope when they're in a manic stage.
"They turn to expressive ways in creativity, music and art and performance," she says. "Those outlets are very largely about discharging the negative emotions."
Artists sense the link between their pain and their art and quite naturally fear losing the latter, says Barry Panter, a retired psychiatrist and psychoanalyst who has written books about creativity and madnes.
He suggests at least some creatives become creative because of their disorders, even as a way to deal with them unconsciously. "When artists are dealing with unconscious emotional issues, that creates great pressure inside, and they use their art to deal with those issues," says Panter. "It's a way of externalizing their pain, hoping to gain control and even mastery over it."
Even if they desperately want to feel better, they don't want to give up what they believe is their inspiration.
"They feel that their creativity comes from their darkness, their bottle — the pain is the muse," says Scharff. "But we don't see that played out. Robert Downey Jr. is more successful in recovery than when he was still using. If you can convince them, which we couldn't with (for example) Hemingway, that there is a way out, they can do well."
History's suicide roll call is pretty daunting but it should be remembered that millions suffer from mental illness, most of them are not famous or artists, and most of them don't commit suicide, says Jeffrey Borenstein, president of the Brain and Behavior Research Foundation in New York.
"Over 100 people a day in the U.S. die by suicide," Borenstein says. "The vast majority aren't famous celebrities. Anyone can be affected by mental illness. It's not particularly prevalent in people with very high intelligence or lower."
Moreover, there are success stories in treating suicidal or depressed creative people, at least these days. J.K. Rowling struggled with depression and suicidal thoughts but, as a single mom, knew she had to get help. It worked, and the author of the Harry Potter novels is now the richest woman in Britain.
Nancy Andreasen, a psychiatrist at the University of Iowa, is halfway through her second study of examining the creative brain through neuro-imaging. She points to another success story, poet Robert Lowell, who gave credit to the drug lithium, "this simple salt," he called it, for normalizing his moods and allowing him to avoid sticking his head in an oven like fellow confessional poet Sylvia Plath.
"I've talked to enough highly creative people to know that a majority of them say treatment actually enhances their creativity," Andreasen says. "If you are absolutely manic, you're so disorganized you can't do anything. If you're depressed, you're so immobile you can't do anything. A good state to be in is a normal mood maybe with a little oscillation up and down."
Borenstein notes that rather than giving someone special insight into the soul, depression is more likely to stifle creativity and reduce a person's performance. Some profoundly depressed people can't summon the energy to get out of bed. "Depression can be extremely debilitating," Borenstein says. "It certainly affects a person's level of functioning."
But apparently not Robin Williams when he blazed across the culture. On stage, he was gleeful, rapid-fire and even joyful as a performer; off stage he was so unhappy he hanged himself with a belt in his home. Bonnie Fuller, editor of HollywoodLife.com, says celebrities and performers often differ in their public and private personas.
"Comedians are kind of known for this, for being not necessarily funny when they're off stage," she says. "A lot of them are not particularly extroverted when they're not performing."
She points to the late comic genius Jonathan Winters, who was known to be Robin Williams' hero and mentor. He also was known to be bipolar.
It may be, says Panter, that Williams and Winters were "wired" differently.
"The neuro-synaptic and neuro-chemical pathways in their brains may be different from most brains, and it maybe this contributed greatly to (their) creativity and their genius," he says.
But it's not proven, and maybe it never will.
Andreasen says she hopes the Williams case helps send a message that depression is as common as a bad cold, and most people can recover from it.
"People with mental illness enrich our lives," she says. "It's a terrible thing on the one hand, but on the other hand, Van Gogh, Winston Churchill, Lincoln… there's a long, long list (of those who) have enriched our lives and also had mental illness."
Contributing: Sharon Jayson, Korina Lopez, Andrea G. Mandell, Carly Mallenbaum and Liz Szabo