Do perfectionists have less junk in their cars? Are they more blunt with people who make mistakes than chaotic? Do perfectionists often suffer from a stiff neck due to their chronic stress? Do chaotic people have more joie de vivre?

It is logical that athletes are generally healthier and fitter than sports haters. But are there other effects of sports that have an impact on everyday life? Are athletes less lazy? Are athletes less able to cope with losing? And who is willing to suffer more pain for a good cause?

Are people from the city less able to concentrate than people in the countryside? Do city dwellers have a more positive self-image? Who has a better chance of survival in the Dutch wilderness? And are villagers perhaps nicer than city dwellers?

Are oldest children better at leadership than youngest children? Are youngest children perhaps funnier? And are eldest children more claustrophobic because they were born through a narrower birth canal and if so, has that had lasting consequences?

Are dog people better at lame talk than cat people? Are they also bossier? Can you smell the difference between dog and cat people? And which of the two is better resistant to very dirty things?

We compare the emotional heart people with the rational head people. Who is more empathetic when firing an employee? Who remains calmest after a collision? And if an IKEA cupboard needs to be assembled, who is best to leave it to?