For the philosopher Thomas Hobbes it was clear: “Homo homini lupus.” Man is a wolf to man.

It is a sentence at which quite a few nod in agreement, because Homo sapiens seems to be behaving like a predator more than ever.

But it may not be in his nature at all; he is sick - infected with Toxoplasma gondii.

At least that's what researchers say who have taken a closer look at the blood of business administration students and their choice of subjects.