random

Alex Martelli aleaxit at yahoo.com
Mon Jun 4 10:51:53 CEST 2001


"Nick Perkins" <nperkins7 at home.com> wrote in message
news:V7xS6.126372$eK2.29676821 at news4.rdc1.on.home.com...
    ...
> A: (P implies (not D))
> "Given a powerful army, I could not defeat Napolean"
>
> B: (not (P implies D))
> "Having a powerful army would not ensure that I could..."
>
> truth table:
> P  D   A:(P implies (not D))  B:(not (P implies D))
> 0  0          1                      0
> 0  1          1                      0
> 1  0          1                      1
> 1  1          0                      0
>
> The difference is that statement A is true if P is false,
> whereas statement B can only be true if P is true.
> Therefore, statement B implies that P is false.

I think I'm getting confused.  From the truth table above,
AND for the immediately preceding statement, I would
deduce the _opposite_ conclusion than yours, i.e., "B
implies that P is _true_".  How do you get the "implies
that P is _false_" instead?


Alex






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