What Bertrand Russell demonstrated with his paradox in 1901 is that it is inconsistent to assume that kinds are real, because this assumption ultimately ends in paradox. By this, he actually killed the sanity of 1/3 of humanity.
About 50 years later, the German Nazi biologist formulated “the foundation for phylogenetic systematics”, later called “cladistics”, on the basis of the fundamental assumption that kinds are real. He thus built a temple on loose sand, or rather on a paradoxical contradiction.
This inconsistent assumption is thus not easy to get rid of (like socialism and religions). It doesn’t matter if it is totally knocked down by facts and reality, it does none the less reemerge at eight. It is just as if we humans can’t live without it. It is belief that matters aren’t the way they are.
The battle in biological systematics is thus fundamentally between believers (ie, cladists) and scientists (ie, Linnean systematicians and evolutionary taxonomists). And, this battle is thus actually already won by scientists (ie, Linnean systematicians and evolutionary taxonomists), but the question now is if believers ever will understand it is. A victory is not a victory before the opponent understands that he’s defeated.
Another contribution to understanding of conceptualization http://menvall.wordpress.com/