According to a new book, a healthy balance between optimism and pessimism may help us cope with what life throws at us.
Whether you're an optimist or a pessimist, the new book reveals that you can learn a lot from attempting the opposite attitude.
Neuroscientist Elaine Fox, a visiting research professor at Oxford University, recently published the book Rainy Brain, Sunny Brain - about our ambivalent feelings of optimism and pessimism.
Our negativity is the response of a rational mind and positivity is a delusion, she said, and for most of us, they both act to balance us out.
"Positivity is a delusion. But it is a useful delusion. If we didn't have some sort of optimism we wouldn't ever get out of bed in the morning. But pessimism has its place," the Independent quoted her as saying.
So, when we think positively, are we just tricking ourselves that things will get better? It's a little more complicated than that, said Professor Fox. Aside from getting us out of bed, it can actually help in other areas of life, but not in the way the self-help books might have you believe.
"Where self-help books say, 'just think happy thoughts,' it doesn't work," she stated. But some degree of optimism can work to our advantage, because if we feel more positive, we will take more positive actions, and reap the rewards.
"Optimism helps you with persistence and gives you a sense of control," Professor Fox explained.
More dramatically, positive thoughts can have concrete health benefits.
Professor Fox interviewed the actor Michael J Fox (no relation) as part of her research to find out how he dealt with being diagnosed with Parkinson's, a progressive neurological condition that affects nerve cells in the brain.
This is one of the times optimism can help us through, Professor Fox said - when we are hit by disaster, optimism helps us pick ourselves back up.
In experiments on pain, in which students are asked to keep their hands in a buckets of ice water for as long as they can stand it, students who believe they have been given a painkiller, but have in actual fact just been given a sugar pill, will keep their hand in longer than those who aren't given anything. Scans of their brains show they actually produce a surge of dopamine, a happy chemical, which combats the pain.
This shows that positivity can have immediate physical effects, noted Professor Fox.
But according to Professor Fox, a healthy dose of negativity could help us out, too.
"The amygdala - the fear system in our brain that helps us detect threat and danger is really at the root of pessimism. Pessimism helps us suss out danger in our lives," she said.
And although we're unlikely to need this reaction the same way our caveman ancestors did - for fight-or-flight reactions - fear is still a useful trait.
"A pessimistic outlook would work if you were setting up your own business," said Professor Fox, "to identify risk and avoid it." So, there is a place for pessimism.
"They say the aeroplane was invented by an optimist and the parachute was invented by a pessimist. That's the reason I called the book Rainy Brain, Sunny Brain, because we need both," she revealed.
In her work, Professor Fox found that scepticism, combined with a sort of over-arching optimism, was found in people who were successful in life and who were able to overcome knock-backs.