Classification

The XVII century French botanist Adanson, in his "Histoire naturelle du Sénégal" (I read it in a citation dy Foucault), describes his "Method" for classifying species. He begins with an arbitrary species, he describes thoroughly this species, than he passes to the next and describes only the differences; he then passes to a third species, and describes only the differences with the first two species. Eventually he arrives at a tabel composde only of differential characters among the species that allows to distinguish the "natural families". It is striking that the method is exactly the same of cluster analysis, only without the help of computer power.