On the belief of cladistics

Those biological systematists called cladists believe, actually claim, that there is a single true classification of biological organisms to be found, although Bertrand Russell demonstrated about a century ago that classification leads to paradox. This imagined "single true classification" is thus actually a paradox, independently of what cladists claim, and thus nothing that can be found. A paradox is a contradiction and thus not something that can be found.

Cladists' claim has, however, created confusion in biological systematics. Biological systematists are no longer sure of what they're doing. Take for example a cod, is it surely a cod or in specific question? What does biological systematics assume and know, respectively?

The belief of cladistics has thus really messed things up in biological systematics. This mess is thus due to an exchange of understanding with belief, probably due to to a lack of understanding. Where the understanding ends takes the belief at.