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Propositions and Connectives, a la shmooop.

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Here's a proposition: You will say "yes" when I ask you to marry me.

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Well, yeah, not very romantic but it's a mathematical proposition otherwise known as a statement.

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And well, many nerdygirls and guys would actually find this a nifty way to ask for a lifetime

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of marital bliss but that's a different story.  A proposition or statement is an equation

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that is either true OR false - but not both. There is always an equating delimiter in there

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- like an equals sign a greater than/ less than thingy or other similar vehicles to compare

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2 values.  in this case, the gal is either gonna say

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<girly voice> I do <reg> or she'll say <well it's been lovely but.... I gotta go...> in

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which case the statement is then false. There is no <well, maybe when you get a real job>

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option. 

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Some other propositions - 6 plus 4 is 10 - true;   6 plus 4 is 20 – false. 6 minus 4 is

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2 – true; 6 minus 4 is infinity squared… uh, false.

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OK so thats propositions. What about connectives? Well, connectives... connect. So think about

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our big question popping here: 

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p: you will say 'yes' q: when i ask you to marry me

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the 3 flavors - uh  no there are only 3 connectives: that is…

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negation:   NOT p as in... i will NOT say 'yes' when you ask me to marry you

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the 2nd flavor is called conjunction…

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as in... you will say 'yes' when i ask you to marry me AND 6 plus 4 is 22. BOTH of these

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conditions have to be true for the statement to be true. so in the first part, there's

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a conditional element - will she or wont she?

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but for this statement to be true, she has to in fact say yes when he asks AND he has

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to work for the congressional budget committee because thats the only place on earth where

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6 plus 4 is 22. otherwise that 2nd element is always false and so the proposition or

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statement in toto is false....    

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ok the 3rd flavor is called disjunction.

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like.. dis junction and dat junction

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but DISJUNCTION is just another $5 word for... Or.

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that is... the statement is true if EITHER condition is met - like... condition a: you

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will say 'yes' when i ask you to marry me;   OR   6 plus 4 is 22.  

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the proposition is true under the 'laws' of disjunction because the gal cartoon really

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loves this statue dude and well, they wanna make babies.

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yeah, as soon as possible - we know, we know.... so since the first part is true it doesnt

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matter that the second part is false - the condition of either one OR the other being

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true is met and the overall proposition is true. 

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Guess they don’t have to worry about their kid being…statuesque…

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