The Unding

5.5421 Dies zeigt auch, dass die Seele—das Subjekt etc.—wie sie in der heutigen oberflächlichen Psychologie aufgefasst wird, ein Unding ist.

This strange being, the Unding, is translated as… well, our logicians see the negation inside (literally Unding is a Nonthing) and extricate it:

Ogden: This shows that there is no such thing as the soul

Pears: This shows too that there is no such thing as the soul

At least Pears does not forget the auch (too). But both translators ignore that, in German, Das ist ein Unding! is just an idiomatic expression. Unding here means an "absurd thing". It may be a law, a rule, an order: it is judged as being against nature, against morals, against reason. And yes, according to the Grimms, Unding may also mean "ghost", "monster", "phantom". As it seems, Wittgenstein is getting polemic here.

For our purposes it would be sufficient to translate Unding as "absurdity".