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?

What does it say about you if you live above or below the major rivers? Are people with a soft G perhaps more honest? Are people with a hard G really such misers? And is the prejudice that northerners are less sociable than southerners correct?

How do you change when you have children? Is it easier for people with children to ignore themselves? Do they cry more quickly? And are they better able to complete a difficult task successfully?

Once upon a time, 'nerd' was almost a swear word, but nowadays it is increasingly seen as cool. But how do you recognize nerds? Are nerds less likely to ask for help when they have problems? And are they really that socially awkward? Or are nerds actually just as herd animals as the rest?

Spirituality is hot. But what does it say about you if you are spiritual? Are you less inhibited compared to your rational fellow man? Are spiritual people perhaps also easier to scam? And who is best to have at your deathbed at the end of your life: someone who thinks very down-to-earth about life and death, or someone who is very spiritual?

Smartphone addiction is a major social problem. What does it do to you if you sit on Instagram and tiktok all day? Does that give you a shorter attention span? What does it do to your health and your body? And might it also have advantages?

Some people see bears on the road everywhere. Others don't worry about anything. But who sees the world more realistically? Who performs better under pressure: worriers, who are afraid of making a fool of themselves, or happy eggs, who avoid all criticism? And can happy eggs also make excuses when things go wrong?