When did ‘sine qua non’ become posh?

Sir, – Further to "Micheál Martin ready for battle with new generation of rivals" (May 17th), I was struck by your political correspondent Harry McGee's apologetic description of sine qua non as "posh"! I was also surprised by his insinuation that Michael Noonan had lacked "fire in the belly".

Res ipsa locquitor, I say – and I hope that doesn't sound too posh. – Yours, etc,

NOEL MURPHY,

Dublin 2.