“And/or” — just plain dumb?

Over at Writing Matters, Leslie O’Flahavan cites five on-line style guides to support the proposition that “using ‘and/or’ in a sentence is just plain dumb.”

I wouldn’t go so far as to call it “plain dumb.” I do try to avoid it myself, because there are better ways to express the same idea. Logically, the disjunctive includes the conjunctive, so or has the same meaning as and/or. If you’re dealing with an illogical situation where or means one or the other, but not both, then write “A or B, but not both.” If you want to make it crystal clear that your situation conforms to normal logic, write “A or B, or both.” See Garner’s Modern American Usage 45 (Oxford 2003).

Comments

[Rao H D]

This hybrid term has been referred to as “that befuddling, nameless thing, that Janus-faced monstrosity, neither word nor phrase, the child of a brain of someone too lazy or too dull to express his precise meaning, or too dull to know what he did mean.”
--Bryan A Garner, A Dictionary of Modern Legal Usage

[peter]

Okay, you've given me the solution to the conundrum I asked about on your other blog: what if you have no confidence the reader will construe the disjunctive to include the conjunctive too. From now on, it's "A, B, or both" for me. (And isn't that an even more concise way to do it?)

[Stephen R. Diamond]

Does the English "or" include conjunction, like the "or" of mathematical logic? Linguist Geoffrey K. Pullum agrees with your affirmative answer. I think the question is itself interesting, although it has only slight practical significance, and I disagree with you and Pullum in "The best that can be said for ‘and/or’: It isn't necessarily stupid." (http://tinyurl.com/yb6nh4b)

[BL1Y]

I agree with Peter. Part of being a good writer is interpreting ways in which your reader might misunderstand you. You can't assume that your reader is a logic whiz.