Editing 1033: Formal Logic

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| title    = Formal Logic
 
| title    = Formal Logic
 
| image    = formal_logic.png
 
| image    = formal_logic.png
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| imagesize =
 
| titletext = Note that this implies you should NOT honk solely because I stopped for a pedestrian and you're behind me.
 
| titletext = Note that this implies you should NOT honk solely because I stopped for a pedestrian and you're behind me.
 
}}
 
}}
  
 
==Explanation==
 
==Explanation==
This comic is a riff on bumper stickers that say "honk if you love ____". Here, the subject is {{w|Mathematical logic|formal logic}}, but the word "if" is replaced with a formal logic term "{{w|If and only if|iff}}," which means "if and only if".
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The key part of this comic is "IFF", which in {{w|formal logic}} means "if and only if""If and only if" represents a formal logic connector that the result is that the truth of either one of the connected statements requires the truth of the other, i.e., either both statements are true, or both are false.  In the comic, if someone honks at this car, it means they like formal logic, there is not any other possible reason per this bumper sticker. (As we see in the image text.)
  
"If and only if" sets a condition which must be met before a procedure is allowed. In this case, you must love formal logic (condition) in order to be allowed to honk (procedure). The title text further elaborates on this, saying in essence: "Don't honk at me just because you're impatient that I stopped for a pedestrian."
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The joke is the contained self reference. You have to love formal logic to take the sticker serious and honk for exclusively that reason.
  
The joke is the contained self-reference. You have to love formal logic to take the sticker seriously and honk for exclusively that reason. In fact, by logic you MUST honk if you love formal logic. The title text reveals the sticker is actually there to stop people from honking at him altogether, because Randall understandably hates it when he yields for pedestrians only to get honked at by some impatient driver behind him; the ONLY reason you're allowed to honk is to declare your love for formal logic.
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But if you don’t love formal logic you would dislike the sticker at all and try to do something contradictory. And now the problem begins: If you don’t honk to contradict the sticker completely you automatically follow its instruction. So, there is nothing you can do except starting to love formal logic.
 
 
==Transcript==
 
:[The rear end of a car (with an unreadable license plate), with a bumper sticker above the tailpipe to the right:]
 
:Honk iff you love  
 
:<big>formal logic</big>
 
  
 
{{comic discussion}}
 
{{comic discussion}}
 
[[Category:Logic]]
 
[[Category:Math]]
 

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