Difference between revisions of "704: Principle of Explosion"

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[[Cueball]] explains the {{w|principle of explosion}}, a classical law of logic, that says that if you start out with propositions ({{w|axiom}}s) that contradict each other, it is possible to derive (prove) any statement you want in the language you are working in, true or false. (In math for example, if you assume that √2 is a rational number, you can 'prove' things that are obviously false, such as the fact that some numbers must be both even and odd. Consequently, you can draw the conclusion that √2 must be an irrational number (provided such a thing exists at all! - luckily, it does and obeys the same calculation rules as for rational numbers; this is how {{w|proof by contradiction}} works.)
 
[[Cueball]] explains the {{w|principle of explosion}}, a classical law of logic, that says that if you start out with propositions ({{w|axiom}}s) that contradict each other, it is possible to derive (prove) any statement you want in the language you are working in, true or false. (In math for example, if you assume that √2 is a rational number, you can 'prove' things that are obviously false, such as the fact that some numbers must be both even and odd. Consequently, you can draw the conclusion that √2 must be an irrational number (provided such a thing exists at all! - luckily, it does and obeys the same calculation rules as for rational numbers; this is how {{w|proof by contradiction}} works.)
  
This can be seen in a {{w:Truth Table}}
+
This can be seen in a {{w|Truth Table}}:
 
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{| class="wikitable"
 
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Revision as of 00:08, 2 May 2015

Principle of Explosion
You want me to pick up waffle cones? Oh, right, for the wine. One sec, let me just derive your son's credit card number and I'll be on my way.
Title text: You want me to pick up waffle cones? Oh, right, for the wine. One sec, let me just derive your son's credit card number and I'll be on my way.

Explanation

Cueball explains the principle of explosion, a classical law of logic, that says that if you start out with propositions (axioms) that contradict each other, it is possible to derive (prove) any statement you want in the language you are working in, true or false. (In math for example, if you assume that √2 is a rational number, you can 'prove' things that are obviously false, such as the fact that some numbers must be both even and odd. Consequently, you can draw the conclusion that √2 must be an irrational number (provided such a thing exists at all! - luckily, it does and obeys the same calculation rules as for rational numbers; this is how proof by contradiction works.)

This can be seen in a Truth Table:

P ¬P P ∧ ¬P P ∧ ¬P ⇒ Q
T F F T
F T F T

The formula P ∧ ¬P ⇒ Q is true in every possible interpretation. No matter what propositions are substituted for P and Q the implication is true. So if a single example of a contradiction were found, then every proposition would be true, (and simultaneously false).

Cueball's friend then proceeds to misinterpret (perhaps intentionally) that you can derive any fact about the physical world. His formula of propositional logic in the third panel reads "P and not P", where is the formal logic symbol for "and" and ¬ is the symbol for "not". P stands for a proposition. As "P and not P" is shorthand for "P is both true and false", this forms a contradiction from which the principle of explosion can begin. Humorously and to Cueball's bewilderment he then successfully manages to 'derive' his mom's phone number. His mom turns out to be Miss Lenhart (now a Mrs?), and to his vexation she asks his friend out.

Waffle cones are a variety of ice cream cone. The rest of the title text is just more of the main comic's derivation joke, since Cueball's "friend" is apparently a cheap bastard who can't spare five bucks to buy his own ice cream cones. (Unless he is smart enough to exploit the system of universe.)

Transcript

[Cueball is talking to his friend.]
Cueball: If you assume contradictory axioms, you can derive anything. It's called the principle of explosion.
Friend: Anything? Lemme try.
[Cueball's friend is writing on a piece of paper on a desk.]
[Cueball's friend is holding up a piece of paper to Cueball, while holding a phone.]
Friend: Hey, you're right! I started with P∧¬P and derived your mom's phone number!
Cueball: That's not how that works.
[Cueball is looking at the piece of paper, while his friend is talking to someone on a phone.]
Friend: Mrs. Lenhart?
Cueball: Wait, this is her number! How—
Friend: Hi, I'm a friend of— Why, yes, I am free tonight!
Cueball: Mom!
Friend: No, box wine sounds lovely!


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Discussion

Could Mrs Lenhart be Miss Lenhart's mother, perhaps? This makes Cueball-1 Miss Lenhart's brother (and thus possibly "Cueball Lenhart", unless he's a half-brother or step-brother or the like). Of course with provably two Cueballs in this situation (and assuming they aren't twins, unless #2... no, we won't go there) we can't therefore assume that any particular lone Cueball is related. However, if "Cueball is a Lenhart AND Cueball is not a Lenhart" then.... well, lock up your mothers... <smirk> 31.111.50.225 22:01, 7 May 2013 (UTC)

^ genealogy makes my head durt. 103.9.42.158 20:22, 19 October 2013 (UTC)


Hey, what do waffle cones and box wine have to do with each other? Wouldn't the cones just get soggy? Just wondering. Anonymous 18:30, 9 December 2014 (UTC)

This is what I came here to figure out. "Oh, right, for the wine" makes it sound like it's supposed to be obvious. 108.162.210.177 00:51, 28 March 2015 (UTC)
Logically the waffle cones are unrelated to the wine, it's a separate item. -Pennpenn 108.162.250.162 00:55, 18 May 2015 (UTC)
I thought the joke was that Cueball's mother was cheap and tasteless because she enjoys drinking boxed wine out of waffle cones. 108.162.238.172 17:24, 28 September 2015 (UTC)
Using the principle of explosion, boxed wine and waffle cones are very much related, and are essentially the same thing. 108.162.229.210 01:29, 7 August 2015 (UTC)

Gah, unpaired parentheses... 108.162.221.150 05:48, 17 August 2015 (UTC)

I added the end parenthesis, just for you. Although, now I'm wondering if double parentheses are really the best alternative... --Hammy2211 (talk) 17:09, 8 October 2015 (UTC)

There was a community portal discussion of what to call Cueball and what to do in case with more than one Cueball. I have added this comic to the Category:Multiple Cueballs. Since here it is clearly the Cueball that calls the mom who is the protagonist and do the important "talking" of this comic he should be listed as Cueball (if any of them). So have rephrased the explanation to take this into account and also noted that the "friend" also looks like Cueball... --Kynde (talk) 15:44, 24 November 2015 (UTC)

Beret Guy lost his hat? I hope he finds it! 172.70.175.146 02:50, 22 February 2022 (UTC)