(no subject)

[redbird]

The word of the day is "iff": I keep wanting to use it in comments.

Comments

[minnehaha.livejournal.com]

"...when they mean 'necessary and sufficient.'"

Which is the term I hear in philosophy.

B

[king-tirian.livejournal.com]

In mathematical writing, I encounter and write both. One might say "The Axiom of Choice is a necessary and sufficient condition for Zorn's Lemma," but when you're in the middle of an argument, it's much more convenient to have a simple conjunction that you can use as one would other logical connectors like "and" and "or".