Apologia is the defendant's speech in a Greek court of law. The apologist seeks to prove that he measures up to the standards set by the categorist, that he is in fact 'within bounds' and has not been trespassing the borders of legitimacy.
Categoria is the prosecutor's speech in a Greek court of law. The categorist establishes the categories of reality - of truth, of error, and of justice - and invites the defendant to live within and measure himself against these standards.
Christian 'apologetics' is a well-established field (not to say industry). What would a Christian 'categorics' look like?