Since 1978 when the copyright law was changed, books that are less than fifty years old must not be photocopied without the publisher’s permission. Thus, any book that has been photocopied since 1978 without the publisher’s permission must be at least fifty years old.
The reasoning above exhibits a flaw similar to one in which of the following?
Any member of the solar system must be either a planet or a moon, so if an asteroid is neither a planet nor a moon, it must not be a member of the solar system.
Anyone who rides a city bus must buy a bus pass, and since Demetrios has a bus pass, he must be riding on a city bus.
A driver who turns right must signal, so any driver who did not signal must not have turned right.
Anyone who legally crosses a national boundary must have a passport; thus anyone who does not have a passport cannot legally cross a national boundary.
Any wage earner residing in the state must pay state taxes, so since Blodwen pays state taxes, she must be resident in the state.
Flaw:错误假设规则一定会被遵守
B:说坐车一定会买票,所以买票的人一定会坐车。这把遵守规则当做前提了,如果是坐车的一定买票了,则就是那个flaw了。
C:右转一定会打灯,所以没打灯的一定不是右转。有flaw,不一定右转的人都会打灯。
D:人合法过境一定要有护照,所以人没有护照不能过境,没有flaw
E:任何境内居住有收入的人都要纳税,(flaw就是不一定这样的人就会纳税,所以没有纳税的人不一定就是没收入的人)如果说没有纳税的人一定是没有收入的就可以选了
而选项中只有c存在违法的可能性,法律规定右转弯要打灯,但有可能存在人违法不打灯直接右转。“违法”匹配。
D是迷惑选项,很容易忽略掉那个illegally,如果没有这个illegally就是对的,但是有了这个前提,就不存在隐含违法的含义了。
再者可以从结果原因这个角度排除A
从原因结果都发生这里排除D
EB是一个问题——范围大了
C和原文才是一个问题——可能不遵守规则
逻辑:50年以下的书要影印,一定要经过出版商允许;没有出版商允许影印的,一定是50年以上的书
C:要右转的司机一定会打灯;没打灯的,must不是右转
D:要出国的人一定有护照;没有护照的人,cannot出国 (没有must语气那么绝对)
看题目想到这里了,看了选项感觉都一样。。。
D选项强调了legally cross, 所以没有逻辑问题
結論說是must, C是must , D是can not登录 或 注册 后可以参加讨论
gap:谁说一定否legal?c也是
we have no reason to assume that the existence of a rule implies compliance with that rule.