Propositions and Connectives

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Grammar & PunctuationGrammar
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Transcript

00:29

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

00:34

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

00:40

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

00:44

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

00:51

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

00:57

option. 

00:59

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

01:07

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

01:12

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

01:18

our big question popping here: 

01:20

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

01:24

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

01:30

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

01:36

the 2nd flavor is called conjunction…

01:37

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

01:44

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

01:47

a conditional element - will she or wont she?

01:50

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

01:55

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

01:59

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

02:05

statement in toto is false....    

02:08

ok the 3rd flavor is called disjunction.

02:10

like.. dis junction and dat junction

02:14

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

02:17

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

02:22

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

02:28

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

02:32

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

02:35

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

02:40

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

02:46

true is met and the overall proposition is true. 

02:50

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