ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

批判性思维基础:事实与合理性 – 译学馆
未登陆,请登陆后再发表信息
最新评论 (0)
播放视频

批判性思维基础:事实与合理性

CRITICAL THINKING - Fundamentals: Truth and Validity [HD]

(开场音乐)
(intro music)
嗨 我是朱莉安娜·钟
Hi! My name is Julianne Chung,
是耶鲁大学的研究生
and I am a graduate student at Yale University.
今天 我们要聊一聊事实和合理性
Today, I am going to talk about truth and validity.
论证有许多不同的
There are many different good qualities
优点
that arguments can have.
比如 它们能让事情变得更清楚
For example, they can be clear,
它们充满趣味
they can be interesting,
它们更具有说服力 等等
they can be persuasive, and so on,
然而 在本节目中我们仅谈论
In this video, however, we are going to discuss
论证的两个特点
just two good qualities that arguments can have
而这两个特点对我们
that are particularly important for determining
要不要接收论证的结果有很大影响
whether we should accept their conclusions.
第一个就是 一个论证的前提可能是对的
The first is this: the premises of an argument may be true,
换句话说 它们可能与现实相符
that is, they may be in agreement with the facts.
哲学中真理和谬论都是陈述所具备的属性
In philosophy, truth and falsity are held to be
但是论证不是这样
properties of statements, but not arguments.
第二个特点 论证可能是合理的
Second, an argument may be valid.
论证结论与前提逻辑相符时
An argument is valid when its conclusion
它是合理的
follows logically from its premises.
也就是说 只要事实前提能推理出
In other words, an argument is valid
事实的结论 那么
just in case the truth of its premises
这个论证就是合理的
guarantees the truth of its conclusion.
在哲学中 合理性和非合理性
In philosophy, validity and invalidity
是论证的属性
are held to be properties of arguments,
这与陈述不同
but not statements.
为了解这些属性之间的区别
To see the difference between these properties,
看些例子会有所帮助
it will be helpful to look at some examples,
这些例子都跟我好朋友朱莉的名叫斯普利特的狗有关
all of which involve my good friend Julia’s dog, Split.
其中一个例子中的论证
This is an example of an argument
具备正确的前提 同时论证也合理
that has true premises and is valid.
前提1 所有澳洲牧羊犬都是狗
Premise (1): All Australian Shepherds are dogs.
前提2 斯普利特是澳洲牧羊犬
Premise (2): Split is an Australian Shepherd.
结论是 所以斯普利特是条狗
Conclusion: Therefore, Split is a dog.
在这个论证过程中 不仅前提是对的
In this argument, not only are the premises true,
结论也是根据前提条件逻辑推导出的
but the conclusion follows logically from them.
下一个例子中的论证具备正确的前提条件
Next is an example of an argument that has true premises
但是论证不合理
but is not valid.
前提1 所有的狗都是动物
Premise (1): All dogs are animals.
前提2 所有的猫都是动物
Premise (2): All cats are animals.
结论 所以所有的猫都是狗
Conclusion: Therefore, all cats are dogs.
这个例子中 前提很明显是对的
Here, the premises are obviously true,
但是结论不是从前提中逻辑推导出来的
but the conclusion does not follow logically from them.
当然啦 这个论述很明显不成立
Of course, this argument is clearly unacceptable,
因为它的结论 明显错误
because its conclusion is obviously false.
然而 有时论证有正确的前提
However, sometimes argumentscan have true premises,
也有正确的结论
as well as true conclusions,
但是却不合理 因为
but still be invalid because the conclusions
结论不是从前提条件中逻辑推导出来的
do not follow logically from them.
这就是一个这样的例子
Here is an example of such a case.
前提1 所有的狗都是动物
Premise (1): All dogs are animals.
前提2 所有澳洲牧羊犬都是动物
Premise (2): All Australian Shepherds are animals.
结论 所以所有的澳洲牧羊犬都是狗
Conclusion: Therefore, allAustralian Shepherds are dogs.
正因为如此
Because of this, it is important
我们要仔细确保
that we are careful to ensure
结论是从论证前提中推导出的
that the conclusion really does follow
这一点很重要 当我们评估
from the premises under consideration
论证的时候 要考虑到这一点
when we are evaluating an argument.
现在我们看看这个论证
We are now going to look at an argument
它至少有一个错误的前提条件 但它是合理的
with at least one false premise that is valid.
前提1 你不能教会老狗新的把戏
Premise (1): You can’t teach an old dog new tricks.
前提2 斯普利特是条老狗
Premise (2): Split is an old dog.
结论 所以你不能教会斯普利特新的把戏
Conclusion: Therefore, you can’t teach Split new tricks.
你瞧 第一个前提是错的
Here, the first premise is false,
但是说理过程是合理的 因为结论
but the reasoning is valid, because the conclusion
是从前提中有逻辑地推导出的
follows logically from the premises.
注意啦 正如上一个例子
Notice, too, that just as in the last example,
论证的结论可能碰巧是对的
the conclusion of this argumentmay happen to be true,
尽管此时的论证没有成立
although the argument does not establish that it is.
好 再来看另外一个例子
Alright, just one more example.
这个论证有至少一个错误前提 而且它也是不合理的
This argument has at least one false premise and is invalid.
前提1 我喜欢斯普利特
Premise (1): I like Split.
前提2 训练狗不难
Premise (2): Training dogs is easy.
结论 所以我通过教会斯普利特怎样打滚
Conclusion: Therefore, I’ll win a lot of awards
获得很多奖赏
for teaching Split how to roll over.
这个例子中 两个前提都是错的
In this example, not only is premise two false,
但是结论也没从前提中
but the conclusion does not follow logically
有逻辑的推导
from the premises.
你可能已经注意到 正确和错误
You’ve probably already noticed that truth and falsity,
还有合理性和非合理性
as well as validity and invalidity,
在一个论证中可以以多种组合的形式出现
can appear in various combinations in an argument,
总共有4种组合的可能性
giving rise to four possibilities,
让我们花些时间来复习下
Let’s take a moment to review them together.
可能性1 事实是对的
Possibility one: we may have our facts right,
前提也是对的 我们正确地处理这些信息
our premises are true, and we may use them properly.
说理过程是合理的
Our reasoning is valid.
可能2 事实是对的
Possibility two: we may have our facts right,
前提是对的 但是我们没能正确的处理这些信息
our premises are true,and we may use them improperly.
我们说理是不合理的
Our reasoning is invalid.
可能3
Possibility three:
事实是错的
we may have our facts wrong,
一些前提是错的
some of our premises are false,
但是我们正确处理这些条件
and we may use them properly.
推理是合理的
Our reasoning is valid.
最后 可能4
And finally, possibility four:
事实是错的
we may have our facts wrong,
一些前提是错的
some of our premises are false,
我们处理它们的方式也是错的
and we may use them improperly.
推理是不合理的
Our reasoning is invalid.
当我们评估一个论证时
When we are evaluating an argument,
如果是第一种可能的话 我们应该
we should only accept its conclusions
接受它的结论
if the first possibility obtains.
哲学家把这种论述称为“牢固的论述”
Philosophers call such arguments “sound arguments.”
因为如此 你可能会思考
Because of this, you might be wondering
为什么我们应该对那些前提是错误的
why we should be at all interested
合理的论证感兴趣?
in arguments that are valid, but whose premises are false?
一种答案是 我们通常
One answer is that we are often not
不会知道前提是不是对的
in a position to know whether our premises are true.
但是如果前提是对的 那我们一般都能
But being able to validly infer the conclusions
妥善的从前提中推理出结论
that would follow from such premises if they were true
有时结论会使我们判断出前提是不是对的
sometimes it enables us to judge whether they are true.
这是因为我们通过给定的一组前提 进行合理的推理
This is because validly inferring a conclusion
如果至少有一个前提错误
that we know to be false from a given set of premises
那么我们就可以知道论证是错的
will tell us that one of our premises must be false too.
毕竟 正确的前提通过合理的推理
After all, a false conclusion cannot validly
是不会得出错误的结论的
be deduced from true premises.
思考下下面这个例子
Consider the following example.
约翰有一天给老板打电话
Say that John calls his boss at work one day,
告诉老板他卧病在床
and tells her that he is in bed
得了很重的流感
with a terrible case of the flu.
看起来 他的老板可以用这些信息来
His boss, it seems, could use that information
建立如下的论证
to construct the following argument.
前提1 约翰患了严重流感 卧病在床
Premise (1): John is in bed with a terrible case of the flu.
前提2 如果约翰卧病在床
Premise (2): If john is in bed
得了严重流感
with a terrible case of the flu,
那么他没有在打保龄
then he is not bowling.
结论 所以约翰没在打保龄
Conclusion: Therefore, John is not bowling.
这个论证是合理的
This argument is valid.
结论是从前提中逻辑推理而来
Its conclusion follows logically from its premises.
因此 如果约翰的老板看见他正打保龄
So, if John’s boss were to see him bowling,
那她会得出什么结论呢?
what could she conclude?
看起来前提2没有因这个论据而改变
Premise (2) seems untouched by this bit of evidence.
然而前提1的变动就大了
Premise (1), however, is in danger.
她可能会得出约翰没得严重的流感 也没
She could conclude that John is not in bed
在床上养病的结论
with a terrible case of the flu.
看起来他撒谎了
It seems he lied.
当然 这是非常简单的例子
This is, of course, just a very simple example.
希望这些例子足以说明
That said, hopefully it suffices to show
我们经常通过这样的推理
that we often use reasoning like this
来判断别人说的话是不是对的
to figure out whether claims are true or false.
因此 对于我们判断论证合理与否
Thus, it is indeed often very useful for us to know
确实是非常有用的
whether an argument is valid,
即使我们不知道它的前提是不是对的
even if we don’t know whether its premises are true.
想了解更多有关事实 合理性和严谨性的话
For more information about truth, validity, and soundness,
我强烈推荐你去看保罗的有关合理性的视频
I highly recommend checking out Paul’s video on validity
以及Aaron的有关严谨性的视频
and Aaron’s video on soundness.
字幕是由Amara.org community制作的
Subtitles by the Amara.org community

发表评论

译制信息
视频概述

推理论证的合理性

听录译者

收集自网络

翻译译者

川上川

审核员

译学馆审核团D

视频来源

https://www.youtube.com/watch?v=pCGnyaa5E5g

相关推荐