陈向东逻辑-归纳-不是外向的人也能做演员么

evelyn205205

All actors are exuberant people and all exuberant people are extroverts, but nevertheless it is true that some shy people are actors.

If the statements above are true, each of the following must also be true EXCEPT?

A.Some shy people are extroverts

B.Some shy extroverts are not actor.

C.Some exuberant people who are actors are shy.

D.All people who are not extroverts are not actors.

E.Some extroverts are shy.

答案是B。
我选的是D。因为我认为：所有不外向的人都不是演员这样的说法太绝对了，就把D否决了，因此看到答案是B后，很纳闷。

evelyn205205

Stimulus: All actors are exuberant people and all exuberant people are extroverts

Actors --> exuberant --> extroverts

So Actors --> extroverts.

Contrapositive:
Not extroverts --> not Actors.

-- by 会员 sdcar2010 (2011/7/29 20:09:47)

alright，原命题的正确性和逆否命题一致。
But at the very first glance， I thought it was saying too absolutely.

sdcar2010

Stimulus: All actors are exuberant people and all exuberant people are extroverts

Actors --> exuberant --> extroverts

So Actors --> extroverts.

Contrapositive:
Not extroverts --> not Actors.

evelyn205205

up~

evelyn205205

NN们，好迷惑啊~

evelyn205205

为什么D不是答案，我觉得D的讲法太绝对了嘛。
期待NN~

evelyn205205

迷惑中，望NN指教~

evelyn205205

期待NN！

evelyn205205

困惑困惑

evelyn205205

还是很困惑啊