Of course, others may suggest that it's completely full of all the atoms that made up water and air.

Others still might remind you that atoms are 99.99% empty space,

making the glass...mostly nothing!

But in all seriousness,

can science explain your emotional perspective and outlook on life?

It turns out, it may not be in your control.

Research has shown that those with two long alleles on specific genes controlling for serotonin

are more likely to focus on positive images - like someone enjoying ice cream

- compared to those with a short allele on the same gene,

who are more likely to focus on negative images - like someone being robbed.

Variation in the oxytocin receptor gene can also affect your outlook;

Individuals with two copies of guanine are noted to be more optimistic with higher self-esteem,

while those with copies of adenine were less positive.

So it seems that people may be genetically susceptible to pessimism.

Interestingly,

optimists are less likely to be rehospitalized after coronary artery bypass surgery,

show higher academic achievements and even better socioeconomic status.

But it's not all good; they can overestimate their abilities and underestimate risk.

Pessimists, on the other hand, have a more realistic view of the world, are more cautious when planning for the future and may even live longer.

A landmark study spanning 20 years found that

pessimists use a cautious approach to their finances and health,

avoiding risky behaviours such as smoking and excessive drinking,

ultimately giving them the last laugh - literally - over optimists.

But, statistically, most of us are hardwired to lean towards optimism.

Known as the Optimism Bias and found in around 80% of the population,

we tend to overestimate the probability of positive events occurring in the future,

while grossly underestimating the probability of negative ones.

For example, even though the divorce rate can be as high as 40%,

most newlyweds predict their probability of getting divorced at...0%.

Chances are, when you imagine your future, it's usually better than your current situation.

Furthermore, we often imagine ourselves

as being more intelligent, sociable and honest than other people.

When we look at the brain,

we actually see the left half exhibits increased activity when imagining positive events,

whereas during negative events the right half's activity does increases,

but to a much lesser degree.

This suggests that the brain chooses to ignore

and filter out negative information and focus on positivity.

Our perspective is, whether you're genetically predisposed to see the glass as half empty or half full — don't waste water and just drink the damn glass already!

This actually reminded us of another common saying though,

that “Giving is better than receiving” -

but is that scientifically accurate?

We answered that one over on AsapTHOUGHT

with a special giveaway which you can click here or use the link in the description to check out.

Special thanks to Audible for supporting this episode

and giving you a free audiobook at your choice at "audible.com/asap."

This week we wanted to recommend the book "The Wright Brothers"

which is the amazing story behind the brothers who taught the world how to fly -

while staying optimistic through all the challenges they faced!

You can get a free copy at audible.com/asap

or any other of your choice from a massive selection!

We love them as they are great when you're on the go.

Don't forget to ask your burning questions, and subscribe for more weekly science videos.