suttonstreet-119@yahoo.com さんは書きました:
> On Jul 13, 2:22 am, Eukie_M_SHIRAISHI <ms.eu...@gmail.com> wrote:
>> Select the truths from the following 1) -- 5)
>>
>> 1) If [ if P, then Q ], then there can be the case in which [ if not-P,
>> then not-Q ].
>>
>> 2) If [ if P, then Q or R ], then either [ if P, then Q ] or [ if P,
>> then R ].
>>
>> 3) If and only if [P and not-Q] is a contradiction, [ if P, then Q ]
>> holds true.
>>
>> 4) If and only if there is a case in which Q does not hold true despite
>> P holds true, [ if P, then Q ] does not hold true.
>>
>> 5) If there is a case in which P does not hold true, then P is a
>> contradiction.
> 
> 
> This is easy, just take two Qs, without the mayo, co-mingle with a
> single P at a time for about 5 cycles, take two drams of quinine and
> add to the mix, and then let sit in the sun for about an hour. If the
> sun is bright enough you will soon find that the Qs now hold true and
> the Ps cancel one another out. It may take a few times to get it
> right.
> 
> Marc
> 

Oh No !  You are totally mistaken.