Hi - > From: "Eric Burger" <eburger-l@xxxxxxxxxxxxxxxxxx> > To: "Narten Thomas" <narten@xxxxxxxxxx>; "Saint-Andre Peter" <stpeter@xxxxxxxxxx> > Cc: "IETF discussion list" <ietf@xxxxxxxx> > Sent: Monday, August 29, 2011 3:08 PM > Subject: Re: 2119bis > > I would assume in the text of the document. This paragraph is simply an enumeration of Burger's Axiom: > For every SHOULD, there must be an UNLESS, otherwise the SHOULD is a MAY. I disagree. If the "UNLESS" cases can be fully enumerated, then "SHOULD x UNLESS y" is equivalent to "WHEN NOT y MUST X." (Both beg the question of whether we would need to spell out that "WHEN y MUST NOT X" is not necessarily an appropriate inference.) RFC 2119 SHOULD is appropriate when the "UNLESS" cases are known (or suspected) to exist, but it is not practical to exhaustively identify them all. Let's not gild this lily. Randy _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf