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Edited on Sun May-11-08 03:40 PM by lynyrd_skynyrd
Allow me to teach the people unfamiliar with logic a simple lesson.
A implies B is does not necessarily mean B implies A.
Usually, we use a little arrow to mean "implies". It looks like this: -->
If I write A --> B, that is a logical expression that means (loosely) "If A is true, then B is true", or put more succinctly, "A implies B".
I can also write a similar expression: B --> A. This means - you guessed it - "If B is true, then A is true".
Now, here is the important lesson. There are certain circumstances when (A --> B) =/= (B --> A). I used the =/= symbol to mean "not equivalent to".
Replace "A" with "One is a racist" and "B" with "One will support Hillary or McCain".
Or Replace "A" with "One is a sexist" and "B" with "One will support Obama or McCain".
What this all boils down to is the following statement in plain english:
A racist will support Hillary or McCain, a sexist will support Obama or McCain, but that does not mean one who supports Hillary is a racist, nor does it mean one who supports Obama is a sexist.
Super duper bonus lesson!
An idiot will support McCain. And a McCain supporter is an idiot.
We write the above using the "equivalent" symbol: ===
"One is an idiot" === "One supports McCain".
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