And yet you happily write "debt" which came into English via the French "dete" as "det" without the "b", and which was artificially inserted for no good reason in the 18th century to make it look more like the original Latin.
Talking about correct when it comes to using a "z" or an "s" is a foolish enterprise, because different words have different roots and to be strictly etymologically accurate you would have to vary depending on word. Either can be used because either are correct.
And yes, Joao, I know you were - but I didn't refer to either, I talked about the use of Latin rules in grammar as it pertains to English.