Here a pretty simple puzzler. Can you find a mistake in Alex‘s logic (taken from an October 9, 2000 strip)?
The usual Freakonomics schwag to the first commenter to post a nice, quotable answer.
(Hat tip: Sparky Clark)
Freakonomics Quiz: Doonesbury Logic
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Not being an independent does not mean that one doesn’t have a mind of his own. if p then q does not imply if not p then not q.
I believe the correct statement would be: if you don’t have a mind of your own, then you are not an independent.
i’m trying to think of something to say, but i’m at a loss
My enemies enemy is not necessarily my friend. Nothing keeps independents from being as brainless as party members.
An independent actually means you have no mind at all.
He’s making an inverse error. He’s saying that if you are p, then you are q, therefore if you are not p, the ellipses imply not q. That’s like saying if you’re from Chicago, you’re from Illinois. And if you’re not from Chicago, then you are not from Illinois.
Sorry the grammar on my last post was off, here’s a fixed version: “An independent actually has no mind at all.”
Being in the party and being stupid are not mutually exclusive, one can not be in the party and also be stupid.
“Conversely” would require you to start with the ‘then’ part of the initial ‘if -> then’ proposition.
i.e. Alex should say, “Conversely, if you do not have a mind of your own…”