Logic: "I Said What I Said" (LSAT)

 

Why am I sharing this meme? Someone asked a question on an LSAT message board and it got me thinking. This is an important thing to understand about logic: statements say what they say and they say nothing about what they don't say. That's vague, so let me explain.

The question posed on the message board was something like the following:
"We're told that whenever K is in the fall, O is in the fall. But can O be in the fall by itself, or will K always follow O into the fall?"

Specifically, in the LSAT prompt, we're told that if K is in the fall then O is in the fall. Since it said that, that'll be true. Whenever K is in the fall, O will also be in the fall. The statement says what it says. 

But were we told what happens whenever O is in the fall? Nope. The only thing we know about O (from this rule) is that it's forced into the fall if K is in the fall. But if K isn't there, maybe O is there, maybe O isn't there. Who knows! So to answer the question, yes, O can be in the fall by itself. It doesn't mean it will be, but it can be. We simply don't know because the statement said nothing about it. In short, remember that for purposes of logic, a statement says what it says.