Monty Python told us to 'always look on the bright side of life', but it seems optimism isn't as ingrained in human nature as previously thought, a new study claims.
Researchers have found that humans aren't predisposed to optimism, nor do we go around with 'a pair of rose-tinted glasses' – a belief that may have biased the findings of previous studies.
The experts cast doubt over past research supporting the existence of 'irrational optimism bias' – that humans innately have a feeling that everything will be alright.
Glass half full or half empty? A 'sizeable body of literature' suggests people's belief updating - beliefs to take into account a new piece of information - is optimistically biased, such that their beliefs are updated more in response to good news than bad news. The new research paper refutes this idea, however
The new study was carried out by researchers at the University of Bath, University College London, and Birkbeck, University of London.
The authors are not saying that irrational optimism bias doesn't exist, but that an assumption that it's an innate part of human nature may have affected the accuracy of previous optimism studies.
They say prior scientific studies have generated 'false positives' – data patterns that look like people are being over-optimistic, where no such bias exists.
'Our experiments show that the method commonly used to evidence such optimism is flawed, giving rise to "optimistic" belief updating where optimism is not possible,' said study author Jason Burton at Birkbeck.
'This is not to say that optimism bias cannot exist in the real world, but that new improved methods are needed.
'Essentially, current methods return false positives.'
For their study, the researchers conducted several experiments using a methodology that has been widely accepted in past optimism research – known as 'the update method'.
This method involves participants estimating their chance of experiencing a life event and then re-estimating it after being provided with the average person's actual chance of experiencing the event – known as 'belief updating'.
Typically, this has been done with negative life events, like contracting a disease or getting a divorce – in other words, various forms of bad news cases that would elicit a strong emotional response.
Humans aren't predisposed to optimism, nor do we go around with 'a pair of rose-tinted glasses' (stock image)
For example, a participant might be asked to estimate their chance of experiencing a negative life event, like getting divorced, to which they might reply 5 per cent.
They're then presented with the actual proportion of the general population that gets divorced in their lifetime – 45 per cent – before updating their belief.
Here, the bad news of finding out the chances of divorce are higher than expected is a form of 'undesirable information'.
'Trials on which participants receive desirable information typically elicit greater updates than trials with undesirable information, which is interpreted as evidence of optimism in belief updating,' the researchers explain in their paper.
For this new study, the researchers tested the same 'update method' but removed the emotional element.
They instead used neutral non-emotional examples, such as participants estimating the