But some wonder whether that "little spark" might have given the manic comedian not only his quick wit, but also a path to depression.
There's a long-held belief that comedians like Williams are more prone to depression — and that their creativity is driven, in part, by the condition.
Andy Nulman, president and co-founder of the Just For Laughs comedy festival, said one of his first reactions Monday night, upon hearing of Williams's death, was "here we go again."
He rhymes off a list of comedians who have died of overdoses or suicide, including stand-up comedian Mitch Hedberg, known as the master of the one-liner, who died of a drug overdose in 2005, and Richard Jeni, a frequent guest on The Tonight Show, who committed suicide in 2007.
"I could keep going. Friends of mine. People who I've worked with. Colleagues who have died self-inflicted deaths or drug overdoses, which you also say is a self-inflicted death," said Nulman.
Williams' personal assistant discovered the 63-year-old actor-comedian's body in his California home early Monday, in what police called an obvious suicide.
It was a tragic ending for a man considered a giant in the comedy world, and news of his death spurred other comedians to come forward with their candid stories of depression.
Dave Foley, who shot to fame as part of the Kids in the Hall comedy troupe, tweeted about his own battle with depression, saying he's suffered from it most of his life and has been undergoing treatment for over 18 years.
"It's terrible to imagine the pain Robin Williams felt," wrote Foley. "I wish he found a better solution."
Big Daddy Tazz, a Winnipeg comedian who says he has been inspired by Williams's manic energy, said that as someone who has dealt with depression himself, and now incorporates that history into his stand-up routines, news of the death hit him hard.
"I was shocked when I heard that he died, but I felt like I'd been hit in the chest with a hammer when I found out that he'd taken his own life," said Tazz.
"The worst part about depression is it lies to you, and that little gremlin that lives in you makes you feel like nobody cares about you and the only way out is to take your life because that's way better than living with the pain."
The 'sad clown' stereotype
But are comedians' madcap antics just a façade for a darker truth?
A study published this January in the British Journal of Psychiatry suggested that comedians possess higher levels of psychotic characteristics than the average person.
Indeed, the characteristics needed to elicit a chuckle are similar to those found in people with schizophrenia and bipolar disorder, the study suggested.
"Although schizophrenic psychosis itself can be detrimental to humour, in its lesser form it can increase people's ability to associate odd or unusual things, or to think 'outside the box'," Oxford University professor Gordon Claridge, the study co-author, was quote in The Guardian as saying.
Other studies have also examined whether comedians are more likely to use humour as a defence against anxiety, or if they became class clowns as children to deal with, say, chaotic home lives.
Then again, U.S. anthropologist Gil Greengross found in a series of tests over the years that comedians don't have any more childhood problems than others.
None of the studies are conclusive, but there's a persistent assumption in some circles that comedians are more prone to depression.
In an article for the online magazine Slate, Humor Research Lab director Peter McGraw and writer Joel McGraw suggest that the notion of comedians as unhinged may derive from the founder of stand-up comedy, Charley Case. The African-American vaudeville performer of the 1880s or '90s lived a troubled life and suffered a nervous breakdown.
Or perhaps it's the act of comedy itself — comedians getting on stage and revealing their quirks and their outlandish stories – that contributes to their being viewed as depressed or disturbed.
Vancouver comedian David Granirer, author of The Happy Neurotic and the founder of Stand Up for Mental Health, rejects any suggestion that comedians are more prone to depression or other mental-health illnesses.
"I think in some ways it's a stereotype, like the 'sad clown'," said Granirer. "There's so many different people who do comedy for so many different reasons.
"A lot of people, not just comics, use humour to cover up their sadness or pain," says Granirer. But, he adds, humour can also help them cope.
That healing side of humour is built into our lingo. "Laughter is the best medicine," people often say, and many are quick to point to "comedy as therapy."
The other side of comedy
Granirer himself uses comedy as an antidote. His program Stand Up for Mental Health is aimed at helping people deal with mental health issues by teaching them stand-up comedy.
Humour can help individuals reduce the internalized stigma and shame they feel about the illness, he says. Instead of locking themselves into a room in a funk, they mine their experiences for comedic gold.
The effect has been transforming for some. One young man, Robbie Engelquist, who joined the group in his early 20s, went from a sullen man in his early 20s refusing to make eye contact with others to becoming one of the program's comedic stars and later on, a rapper.
"What people like about Stand Up for Mental Health is I don't treat them like someone with a mental illness, like someone with something wrong with them. I treat them like a comic," says Granirer.
As someone who suffers from depression himself, Granirer also employs humour as a coping mechanism in his own life.
"Comedy got me through some of the really, really bad times in my life," said Granirer. " If I can find something, some humour in something during the day, then at least my day has some meaning."
He also notes that while Williams often spoke in his stand-up routines about his struggle with alcoholism and cocaine abuse, admitting "I was shameful, did stuff that caused disgust," but he rarely mentioned his battles with depression.
"It's way cooler to say, 'Oh, I used to drink too much,' and 'Man, I snorted a tonne of cocaine. Woohoo, those party days!'" says Granirer. "As opposed to saying, 'I have really bad depression. There are days when I can't get out of bed. There are days when I want to end it all.' "
In the end, Granirer and other comics hope Williams' death spurs a more public discussion about depression, not only in the world of comedy, but outside as well.
"It's incredibly sad because of the fact that these are the people who make you laugh and you realize how troubled they are," said Nulman. "But it's not just them. And that's really the key point here."
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