What is intelligence?
Theoretical physicist and all-around smart guy Albert Einstein once said that "The true sign of intelligence is not knowledge but imagination."
On the other hand, star of hit film Space Jam and minor league baseball enthusiast Michael Jordan (look it up) once said that "Talent wins games, but teamwork and intelligence wins championships."
Either way, if we stand atop the shoulders of both of these two great men, both of whom have defined history in equal measure, we can conclude that concept of intelligence is indeed a thing that perhaps has only a loose definition.
Regardless, we've consulted with scholars, scientists and - more importantly - scoured inane listicles in the deepest, darkest corners of the internet to bring you the five most common characteristics shared by intelligent people.
1. Intelligent people stay up late.
Some people stay up late, some people are up and going about their day at the crack of dawn. And according to Psychology Today, what makes the difference between the two could be your smarts.
Virtually every species on the planet - from humans to single cell amoebas to even the Bobbit worm - have a daily life cycle called the circadian rhythm, which is regulated by nerve cells called the suprachiasmatic nuclei in the anterior hypothalamus. Bear with us now...
Scientists found that in most mammals the circadian rhythm is regulated by a set of genes. However, we humans have a unique ability in that we're able to override our body clock and disturb our circadian rhythm. Still with us?
It means that for humans, our circadian rhythms are not just down to genetics, which is why we can determine things like when we wake up and go to bed - whether we're night owls or early birds getting the worm.
Psychology Today concludes - or at least, suggests - that considering throughout the annals of time, our ancestors based their circadian rhythm around the natural light provided by the sun (as in today, they would wake up just before dawn and rest just after dusk in order to make the most of the daytime), one could make a hypothesis that nocturnal activities are a result of evolution, and thus, more intelligent folk are the ones who break from the circadian rhythm and go to bed later. Psychology Today actually ran a study on young Americans and found that their data backed up their hypothesis - that the kids with the higher IQs went to bed later.
Something to think about next time you're lying awake way after your bedtime, anyway.
2. Intelligent people didn't have sex as teenagers.
Honestly. This isn't just something that people who don't get much sex tell themselves to feel better. Researchers from the University of North Carolina found that adolescents with an IQ lower than 70 or higher than 110 are more likely to be virgins.
According to Penn State Collegiate, the study was conducted by Mariah Mantsun Cheng, a research associate, and J Richard Udry, professor of maternal and child health and sociology, both from the university. They discovered that 39.8 per cent of boys with an average IQ score had already had sex, compared with 29.9 per cent of boys with an IQ above 110.
And according to their research, 100 is the magic number, as an adolescent with this IQ score was 1.5 to 5 times more likely to have had sex than an adolescent with an above average score of around 120-130.
3. Intelligent people don't smoke cigarettes.
This seems like one to file away under 'bleeding obvious', but there's actually facts, figures and research to show that smoking makes you dumber.
The Sheba Medical Center at the Tel Hashomer Hospital in Israel conducted a study of 20,000 young adults and found that the heavier the smoker, the lower the IQ. And those who smoked at least one packet of cigarettes a day averaged seven and a half IQ points lower than those who don't smoke.
The study also found that brothers scored differently depending on whether or not one of them smoked.
"It's very clear that people with low IQs are the ones who choose to smoke," said Dr Mark Weiser, who led the research. "It's not just a matter of socioeconomic status - if they are poor or have less education."
It's also been suggested that the results of this study confirm a previously-held conviction that those with lower IQs make poorer decisions regarding their health in general.
4. Intelligent people are politically liberal and don't believe in God.
This isn't posturing or jumping on a soapbox to preach lefty ideals, this is literally what was discovered in a study called Why Liberals and Atheists Are More Intelligent, published in Social Psychology Quarterly by Satoshi Kanazawa in 2010.
The study found that The Savanna-IQ Interaction Hypothesis, derived from the Savanna Principle and the theory of the evolution of general intelligence, suggests that the more intelligent you are, the more likely you are to adopt values of liberalism, atheism and, in men, sexual exclusivity.
However, the same study found that general intelligence may have no effect on friendship and family issues, like children and marriage, so while you might be a super smart social justice warrior, you're possibly also cripplingly alone.
5. Intelligent people know what irony is.
"An old man turned 98, he won the lottery and died the next day." No, Alanis, that's not irony, that's just bad luck.
"It's a black fly in your Chardonnay." No, Alanis, that's not irony, that's just unfortunate.
"It's a death row pardon two minutes too late." That's not irony, Alanis, it's bad timing with fatal consequences and also cause to launch a full-scale public inquiry into the clearly glaring errors deeply rooted in the judicial system.
Irony is defined in the Oxford Dictionary as:
A state of affairs or an event that seems deliberately contrary to what one expects and is often wryly amusing as a result.
And there's nothing wryly amusing about people dying, Alanis, nor about ruining perfectly good Chardonnay.