"If-Then" Tables Explained
Sans Doute
(Part 5)
So far we've filled in three rows of the "If-Then" Truth Table.
Truth Table: If-Then Statements | ||
QH | RC | QH → RC |
TRUE | TRUE | TRUE |
TRUE | FALSE | ? |
FALSE | TRUE | TRUE |
FALSE | FALSE | TRUE |
And now let's pick another card.
And we get something weird:
Yep. We've picked the Queen of Hearts - but it's a black card.
And now what do we do?
Well, we did select the Queen of Hearts. So the antecedent is TRUE.
QH ≡ TRUE
But it's a black card. So in this case, the consequent is FALSE.
RC ≡ FALSE
So our entire statement:
QH → RC
... has the assignment:
TRUE → FALSE
Now that I've picked the right card but of the wrong color, is my original statement:
QH → RC
... TRUE or FALSE?
Clearly it's FALSE. I had said, IF I select the Queen of Hearts THEN it will be red. But the card was black. In other words, I fulfilled the required condition, but the outcome was not what I said it would be. So the entire statement is FALSE.
So we can now fill in the last incomplete row. And we get the final Truth Table:
Truth Table: If-Then Statements
QH | RC | QH → RC |
TRUE | TRUE | TRUE |
TRUE | FALSE | FALSE |
FALSE | TRUE | TRUE |
FALSE | FALSE | TRUE |
Now to some this type of argument is convincing. But to others, it's still a bit iffy. There is, though, another way to show that this Table - as the commercials say - really, really works. Which you can finally see, if you click here.
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