熱血背包客莊ㄟ

Lecture 3- setting out logical book style 

by Marianne Talbot, university of Oxford 

Here is an argument set out logic book style :

Premises one : it is Friday 
Premises two : Marianne always wears jeans on Friday.
Conclusion : Marianne is wearing jeans. 

The point :

1. It enables us to add suppressed premises ( assumption by author )

2. It enables us to eliminate cross references, irrelevancies, and inconsistent terms. 

3. It is much easier to evaluate arguments, but no evaluation.

EX:

1. Since Manchester is north of Oxford and Edinburgh is north of Manchester,

   Edinburgh is north of Oxford.

Premises one : Manchester is north of Oxford
Premises two : Edinburgh is north of Manchester
Conclusion :  Edinburgh is north of Oxford.

2. Witches float.

 Because witches are made of wood and wood float. 

Premises one : witches are made of wood
Premises two : wood float.
Conclusion : Witches float.

Set of steps for analyzing arguments :

1. Identify the conclusion of the argument.
2. identify each of the premises 
3. Add suppress premises 
4. Remove irrelevancies 
5. Remove inconsistent terms 
6. Remove cross-references (definition of pro-non)

Before identifying premises or conclusion, you need to find the indicators :

so, therefore, then, accordingly, hence, for, since, given, because…….

From which we see that, it follows that, which established that…….

EX:

Since all men are mortal, Socrates is mortal, for Socrates is a man.

so the sentences follow Since and for are premises 

EX:

Socialism was doomed to failure 

because socialism did not provide incentives needed for a prosperous economy.

Premises1: incentives are needed for a prosperous economy (suppress premises)
Premises2: prosperous economy is needed for success (suppress premises) 
Premises3: socialism did not provide incentives.
Conclusion: socialism was doomed to failure.

EX:

Since many newly emerging nations do not have the capital resources necessary for sustained growth, they will continue to need help from industrial nations.

Premises1: many newly emerging nations do not have capital resources 
Premises2: capital resources are necessary for sustained growth
Premiere3: if a newly emerging nation is to sustain growth, and it did not have capital resources, it will need help from industrial nations.(suppress premises)
Conclusion: many newly emerging nations will continue to need help from industrial nations.

Identify the conclusion of this argument 

Well perhaps she didn’t want you to tickle her tummy, or she didn’t realize that was what you are going to do. If she didn’t realize then you obviously went about it in the wrong way. In that case you deserved to get scratched unless you really thought she was such a perceptive cat that she’d understood ‘’ woof-woof “ meant “roll over”. If you thought that you are an idiot. But you are not an idiot, you are just twisted. So if the pool thing did want you to tickle her tummy, you deserve to get scratched.

Conclusion: if the pool thing did want you to tickle her tummy, you deserve to get scratched.(conditional conclusion)

Premise 1: Well perhaps she didn’t want you to tickle her tummy, or she didn’t realize that was what you are going to do.

Premise 2: If she didn’t realize then you obviously went about it in the wrong way.

Premise 3: In that case you deserved to get scratched unless you really thought she was such a perceptive cat that she’d understood ‘’ woof-woof “ meant “roll over”.

Premise 4: If you thought that you are an idiot. But you are not an idiot, you are just twisted.

In order :

Premise 1: Well perhaps she didn’t want you to tickle her tummy, or she didn’t realize that was what you are going to do.

Premise 2: If she didn’t realize then you obviously went about it in the wrong way.

Premise 3: In that case you deserved to get scratched unless you really thought she was such a perceptive cat that she’d understood ‘’ woof-woof “ meant “roll over”.

Premise 4: If you thought that you are an idiot. But you are not an idiot, you are just twisted.

Conclusion: if the pool thing did want you to tickle her tummy, you deserve to get scratched.(conditional conclusion)

There are no suppresses, so removing the irrelevancies

Premise 1: Well perhaps she didn’t want you to tickle her tummy, or she didn’t realize that was what you are going to do.

Premise 2: If she didn’t realize then you obviously went about it in the wrong way.

Premise 3: In that case you deserved to get scratched unless you really thought she was such a perceptive cat that she’d understood ‘’ woof-woof “ meant “roll over”.
You can not remove “in that case”. Because in that case means a condition, equal to “if it is true”

Premise 4: If you thought that you are an idiot. But you are not an idiot, you are just twisted.
it is more like a joke to mock someone

Conclusion: if the pool thing did want you to tickle her tummy, you deserve to get scratched.

In order :

Premise 1: She didn’t want you to tickle her, or she didn’t realize that was what you are going to do.

Premise 2: If she didn’t realize then you went about it in the wrong way.

Premise 3: In that case you deserved to get scratched

Conclusion: if the pool thing did want you to tickle her, you deserve to get scratched.

Removing inconsistent term and cross reference :

Inconsistence :

means that materials that you perform the sentences to replace some specific terms then you should turn the specific terms back. 

Cross reference :

means that contexts or compose in sentences that used to replace the term by pronoun, needing to turn them back to the original terms.

Premise 1: She didn’t want you to tickle her, or she didn’t realize that you are going to tickle her

Premise 2: If she didn’t realize that you are going to tickle her, then you are going to tickle her in the wrong way.

Premise 3: if you are going to tickle her you deserved to get scratched

Conclusion: if she did want you to tickle her, you deserve to get scratched.

Do not evaluate the argument, cuz we ain’t got no there !!!!

We are focus about analyzing the argument, knowing the each sentence playing for, and revealing the structures. 

Formalization :

Premise 1: P or Q
She didn’t want you to tickle her, or she didn’t realize that you are going to tickle her

Premise 2: if Q then R
If she didn’t realize that you are going to tickle her, then you  are going to tickle her in the wrong way.

Premise 3: if R then S
you are going to tickle her in the wrong way then you deserved to get scratched

Conclusion: if (-P) then S
If she want you to tickle her then you deserved to get scratched

這篇主要是在把arguments的結構給分成兩個一個為前提，一個為結論，不做任何的評價，所以當我們在看最後一個範例的時候，會覺得奇怪很不合理，前提跟結論完全沒有連上邊

you are going to tickle her in the wrong way then you deserved to get scratched

你用錯誤的方法騷小貓咪的癢結果被抓傷

If she want you to tickle her then you deserved to get scratched

小動物要你幫他搔癢，結果也被抓傷

想必中間還少了一個隱藏的前提必須加上去，也就是小貓知道你要搔他癢，但是用錯方法了，造成他不了解你再騷他養，所以他抓傷你，活該。整個少一個邏輯鍊，不過professor Marianne並沒有加上隱藏前提，那我就當作沒這事情，先不去評論argument到底合不合理，主要是練習個句子的角色是否抓對。

另外講到的logic book style其中一個重點是找出隱藏前提，這是一個邏輯缺陷，作者直接霸王硬上夠，少講一個邏輯鍊就直接把前提和前提配對起來，這個找到隱藏前提的技巧就可以用來解決assumption的題型

以上來自牛津大學教授上課筆記希望能幫上忙，喜歡，或是不喜歡還是有錯誤，歡迎留言指教，謝謝!!