作者MathTurtle (恩典)
看板logic
标题Re: [讨论] 如果昨天到了明天会变成两天前
时间Wed Feb 25 12:51:47 2009
okok...我去看了一下, 觉得满有趣的, 和哲学中在讨论的时间哲学有些相关。
原文似乎是:
"If yesterday was two days ago tomorrow,
will the day after tomorrow be today or yesterday?"
其实关键在於时态。
首先有个小问题, 为何第一句用 'was'?
按照正常的文法, 第一句的时间是由副词tomorrow给出,
而不是由主词yesterday给出, 所以按文法规定而言可以有:
1. if yesterday will be two days ago tomorrow...
这是最直接的讲法。
意思是, 在明天时, 昨天「是」两天前。
2. if yesterday is two days ago tomorrow...
这样也可以通, 因为未来时态的condition有时可用现在式,
表达对fulfillment的不确定性 (e.g. if it rains, I will stay home).
另一种会用 'is' 的原因是表达tenseless的条件,
也就是单纯呈述昨天(indexical)是两天前(non-indexical)。
3. if yesterday were two days ago tomorrow...
这种讲法也有可能, 这里的were是subjunctive,
基本上是表达与现在事实相反的counterfactual 假设,
不过也不一定要预设与现在事实相反, 单纯只是表达counterfactual,
不过如此的语态後面那句也要改, 就变成:
if yesterday were two days ago tomorrow,
would the day after tomorrow be (or have been) today or yesterday?
好, 现在, 时间哲学当中有两个理论,
tensed theory 和 tenseless theory.
根据tensed theory, if yesterday will be two days ago tomorrow,
(of course it will, but the tensed phrase clearly indicate such a context),
then the day after tomorrow surely will be today, it also will be yesterday,
but on a different day.
根据tenseless theory, if yesterday is two days ago tomorrow,
(the conditional indicates the context where we may translate the indexicals),
then the day after tomorrow is tomorrow (index = tomorrow),
it cannot be today, nor yesterday, and of course it cannot be both.
大概是这样, 我在学时间哲学时, 感受到英语母语人士对时态语感的强列依赖,
如果持定tense theory, 很难理解tenseless theory 的观点,
反过来, 如果持定tenseless theory, 也难理解tense theory 的观点。
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 131.111.224.87
1F：推 aletheia:我不太懂为什麽tensed的时态要用will be 02/25 15:28
2F：推 aletheia:tenseless要用is? 02/25 15:28
3F：→ MathTurtle:tenseless只是陈述material implication中的前件 02/25 16:25
4F：推 hirabbitt:强大...到我看不懂XD 数龟什麽都学吗 02/26 07:06
5F：推 ars1an:你後面的说明我可以理解，但回过头来看反而题目很奇怪 02/26 10:11
6F：→ ars1an:If yesterday "was"..., "will".... 02/26 10:12
7F：→ ars1an:这样的问句是tensed theory还是tenseless theory? 02/26 10:12
8F：推 H45:有人和我一样从 tensed, annd tenseless theory 联想到微软中 03/01 07:10
9F：→ H45:国研究院最新面试题的讨论串吗.... 03/01 07:10
10F：推 hirabbitt:哪题0.0? 03/01 17:07