S.3 /Liberal Studies (2014-2015) / Critical Thinking P.1
Hong Kong Taoist Association
Tang Hin Memorial Secondary School
S.3 Liberal Studies
Chapter 1
Critical Thinking
Teacher’s version
Name: ________________________________
Class: ______________( )
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.2
1. What is Critical Thinking (批判思考)?
Critical thinking refers to clear and reasonable thinking.
Critical thinking is the use of thinking skills and strategies to arrive at an ideal result.
We can use critical thinking to evaluate and analyse arguments, to calculate
likelihood, to make important decision and to solve problem.
(Ku, Hau & Ho., (2009), Package on “The learning and teaching of critical thinking skills” (Senior Secondary), Personal, Social
and Humanities Education Section, C.D.I., E.B.)
REVISION: 5 steps in critical thinking
The following are the steps in critical thinking. Rearrange them in correct order.
A. Identify any logical fallacies in the argument.
找出論述中的謬誤。
B.
Clarify the meaning of the wordings in the argument
釐清關鍵語言的意思
C.
Identify the issue, the conclusion and the reasons supporting the conclusion.
確認議題、結論和支持結論的理由。
D.
Decide whether to accept, reject or suspend judgment on the argument.
對論述作出判斷 (接納、否決或是未能作出判斷)
E.
Evaluate the credibility of the argument.
評估理由和證據的可信度。
C

B

E

A

S.3 /Liberal Studies (2014-2015) / Critical Thinking P.3
2. Identify the issue, the conclusion and the reasons supporting the
conclusion
A.
What is an issue (議題)?
Before we decide whether to accept or reject an idea, we should first identify the issue
being discussed.
An issue is an important question that is in dispute. Different people may have
different views over an issue. They often try to persuade others to agree with them.
B.
Argument (論述), Reasons (理由) and Conclusion (結論)
After identifying the issues being discussed, we have to find out the arguments of the
speaker or writer.
Argument = Reason(s) + Conclusion
Example 1: All human will die. Tim is a human. Tim will die.
Argument
Conclusion
Reasons:
Tim will die.
All human will die. Tim is a human.
An argument is a claim that people put forward and defend with reasons.
The claim that is supported is called the conclusion of the argument.
The reasons are used to provide support to the conclusion.
Conclusion is the “what” in an argument. It tells the reader or listener what to
believe and what to do. There are words and expressions which usually indicate
conclusions. The following are some examples of conclusion indicators:

Therefore,

In conclusion …

Thus …

As a result,

So
E.g. Based on the above reasons, you should work hard in school.
conclusion indicator
conclusion
If the conclusion is the “what” of an argument, then reason is the “why”.
Reason explains why a conclusion is right. Reasons explain why the readers or
listeners should believe that the conclusion is right.
The following are some examples of reason indicators:

Because …

The reasons are …

Since …
E.g. Because Eason Chan is a pop singer, there are many singers who wish to
imitate his style.
reason indicator
reason
conclusion
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.4
3. Clarify the meaning of the wordings in the argument
A. Clarifying the meaning of the wordings
After identifying the issues and the arguments being discussed, we have to make sure
we understand the meaning of the key wordings used. For example, if people are
discussing the issue of setting the minimum wage laws, we have to understand the
meaning of ‘minimum wage’ first.
Besides, we have to check whether the arguments contain any linguistic pitfalls.
B.
Linguistic pitfalls (語言陷阱)
Some people use wordings with obscure meaning (含糊不清的措辭) or even distort
the meaning of words in order to mislead or confuse others. These are called
linguistic pitfalls (語言陷阱). We must be very careful to avoid being trapped by
them.
1. Obscurity (語意不清)
The following are two types of obscurity (語意不清).
(i)
Incomplete meaning (闕義)
E.g.1
Hong Kong people are impolite.
Does it mean that all Hong Kong people are impolite? Or most of the Hong
Kong people are impolite? Or just some of the Hong Kong people are impolite?
The meaning of this sentence is incomplete here.
(ii)
Vagueness (含混)
A term is vague if it has an imprecise boundary.
E.g.2
If you get good results in your examination, I will take you to the
Disneyland.
Different people have different definitions on ‘good results’. Full mark is
absolutely good and zero mark is undoubtedly bad. How about the marks
in-between? The term ‘good’ and ‘bad’ do not have clear boundaries. Thus, the
meaning of ‘good results’ is vague.
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.5
2.
Distortion (概念扭曲)
Distortion means using words in such a way that deviates from its standard meaning.
E.g. 3
Teacher: You did not get an ‘A’ because you were not hardworking.
Student: But I was studying all the time and slept for only 5 hours a day.
Teacher: No. If you were really hardworking, you would have got an ‘A’.
The teacher here distorted the meaning of hardworking as getting an ‘A’. In fact,
hardworking means trying one’s best but does not guarantee that he will get an ‘A’.
3. Empty Content (言辭空廢)
Empty content means any statement that aimed to provide information, but in
fact it provides no information at all.
E.g. 4
It may rain tomorrow or it may not.
E.g. 5
Anything that is large is not small.
E.g. 4 looked like predicting something. In fact, it stated all the possibilities only.
E.g. 5 is also an empty statement. It used the opposite of large to explain what is
large. However, if a student is learning English and does not know the meaning
of large, then the answer ‘anything that is large is not small’ provides some
useful information. In such case we should not say that the answer is empty.
C. Identifying the linguistic pitfalls
Read the following statements. Identify the linguistic pitfalls if any. State the type and
explain briefly.
1. The weather is getting cold because the temperature is dropping.
Type
Empty content
Explanation
The conjunction “because” is used to link the reason and
conclusion. However, in this statement, the meaning of “weather
is getting cold” is exactly the same as “temperature is dropping”.
That means the reason and conclusion here are exactly the same.
So, the statement does not provide any information,
2. An employee of Company X, “Many people will lose their jobs if our company
goes to bankruptcy. Therefore, based on the consideration of public interests, the
government should provide financial assistance to our company.”
Type
Distortion
Explanation
He distorted the meaning of “public interest” as “the
interest of the employees in company X.” The standard
meaning of public interest should be the interest of the
whole society.
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.6
4. Evaluate the credibility of the argument
A. Evaluate the credibility of the argument
In the process of critical thinking, we have to identify the issues and the arguments
being discussed first. We should clarify the meaning of the key wordings used and
check whether there are any linguistic pitfalls afterwards. Then, we have to check
whether the arguments and conclusion are credible.
B.
1.
Deductive argument (演繹論證) and inductive argument (歸納論證)
Read the following arguments. Underline the reasons and put a square around the
conclusion.
Argument A:
Gas expands when heated. X is a gas.
Therefore, X expands when heated.
Argument B:
If it rains, the streets will be wet. The streets are wet now. It must have just rained.
Argument C:
All humans have three stomachs. Dolly is a human. Dolly has three stomachs.
Argument D:
I went every part of the world to collect a certain number of lemons. I collected
10000000000 lemons in total and found that all these 10000000000 lemons tasted
sour. Thus, I believe that all lemons taste sour.
Argument E:
I caught a small fish in this pond yesterday. Today, I caught a small fish again in this
pond. Therefore, I believe that all the fishes in this pond are small.
2. Arguments A, B, C are deductive arguments.
(a) Which of the arguments, A, B or C, must be true?
A
(b) Explain why the other two are not true.
Argument B:
In the first sentence, ‘it rains’ is the cause and ‘the streets will be wet’ is the
consequence. ( I mark )
However, in the second part , of the argument, the cause and consequence are
reversed.
( 1 mark )
There may be other reasons that caused the streets wet. E.g. the streets have just
been washed.
( 1 mark )
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.7
Argument C: The first statement ‘all humans have three stomachs’ is not a fact.
So, the argument is not true.
3. Arguments D and E are inductive arguments
(a) Which of the arguments, D or E, is more probably true?
.D
(b) Explain your answer.
Argument D: the number of lemons collected is large (large sample size) and
the lemons are collected from different parts of the world. On the other hand, only
two fishes were caught in argument E. We cannot draw a general conclusion from
such a small size of sample.
4. DISCUSSION: What are the differences between deductive and inductive
arguments?
DEDUCTIVE
INDUCTIVE
Deductive reasoning is a method to
deduce a certain conclusion from
general rules. (由普遍到特殊)
Inductive reasoning is a method to
find a general rule from a large
number of particular examples. (由
個別到一般)
If all the reasons in a deductive argument If all the reasons in an inductive
are true, then the conclusion _________ argument are true, then the conclusion
must be
is probably
_______________ true.
____________________________ true.
Practice:
Are these inductive or deductive arguments?
1. All fishes breathe with gills. Salmons are fishes. They
breathe with gills.
Deductive
2. All the swans in France are observed as white. All the
swans in Germany are also observed as white. Then, all
swans in the world are white in colour.
Inductive
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.8
C. Evaluating deductive arguments
We can evaluate deductive arguments based on two criteria:
1. Validity (對確度) of deductive argument
A deductive argument is valid (對確的) if it is deductively correct, .i.e. IF all the
reasons are true, the conclusion MUST BE true.
Which of the deductive arguments on p.6 are valid?
A,C
Rewrite the invalid deductive argument on p.6 into a valid one.
Argument B: If it rains, the streets will be wet. It has just rained, the
streets are wet now.
2. Soundness (對當度) of deductive argument
A sound (對當的) deductive argument is a VALID argument with ALL the reasons
being TRUE.
Which of the deductive arguments on p.6 are sound?
A
Which of the deductive arguments on p.6 is valid but unsound? Rewrite it into a
sound one.
Argument C. All humans have one stomach. Dolly is a human. Dolly has one
stomach.
Practice:
Evaluate the validity and soundness of the statements below.
Valid?
1. If he loves me then he gives me flowers.
He gives me flowers.
So he loves me.
2. If it rains, the streets will be wet.
If the streets are wet, accidents will happen.
Therefore, accidents will happen if it rains.
Sound?
Invalid
Unsound
Valid
Unsound
A good deductive argument must be sound (valid and with all
reasons that are true).
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.9
E.
Evaluating inductive arguments
We can evaluate inductive argument based on its strength.
Strength (強度) of inductive argument
Strong inductive argument is an inductive argument in which if all the premises are
true then the conclusion is probably true than false.
(a) Which of the inductive arguments on p.13 is a stronger inductive argument?
Argument D.
(b) Rewrite arguments D and E into stronger arguments.
Argument D: change the word ‘all’ into ‘most of the’.
Argument E: change the word ‘all’ into ‘some of’.
A good inductive argument must be strong and all the reasons supporting the
conclusion must be true.
Practice:
1. If there is a lack of government assistance, life will be difficult for farmers. The
farmers find life difficult, so there must be a lack of government assistance.
(a) Is this a deductive or inductive argument?
A deductive argument
_____________________________
(b) If it is a deductive argument, is it valid? Explain briefly. OR
If it is an inductive argument, is it strong? Explain briefly.
“Lack of government assistance” is the cause while “life will be difficult for
farmers” is the consequence.
( 1 mark )
In the second statement , the cause and the consequence are reversed ( 1 mark )
There is another cause like weather which
farmers” ( 1 mark )
may cause “life will be difficult for
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.10
Therefore, it is an invalid argument (deductively wrong). ( 1 mark )
2.
All the fish John has caught in the river have weighed more than 100 pounds. So,
most of the fish in the river weigh more than 100 pounds.
(a) Is this a deductive or inductive argument?
An inductive argument
_____________________________
(b) If it is a deductive argument, is it valid? Explain briefly. OR
If it is an inductive argument, is it strong? Explain briefly.
We do not have enough information to decide whether it is strong or not.
The strength of this argument depends on the number of fishes John has caught (i.e.
the sample size) and the total number of fishes in that river (i.e. the population size).
If John has caught a large proportion of the fishes in the river, then argument X is a
strong one.
(Strength is directly proportional to sample size)
5. Identify any logical fallacies in the argument
A fallacy is a mistake in logical reasoning.
(謬誤是指思維方式上的錯誤)
The study of fallacies is an important part of critical thinking. Understanding fallacies
help us to avoid them. It also helps us to better explain others’ mistakes in their
arguments. We may divide fallacies into four categories: (李天命博士的「四不架構」)
Fallacies of inconsistency
(不一致謬誤)
These are cases where something inconsistent or self-defeating has been proposed.
(思考或言論有矛盾衝突、自我推翻、不一致等性質)
E.g. When the former chief executive Mr. Tung was asked to comment a TV
program. He said, ‘I shall not comment on such distasteful program.’
Fallacies of inappropriate presumption
(不當預設謬誤)
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.11
These are cases where we have an assumption or a question presupposing something
that is not reasonable to accept.
(把不能視為當然的假設視為當然)
E.g. E.g. Your friend asked you ‘Have your father succeeded in breaking from the
jail?’
Fallacies of irrelevance
(不相干謬誤)
These are cases where irrelevant reasons are being used to support the conclusion.
(理由和結論沒有邏輯關係，甚至毫無關連)
E.g. Sam is a bad person. So, Sam’s argument must be wrong.
Fallacies of insufficiency
(不充分謬誤)
These are cases where the evidence supporting a conclusion is insufficient or weak.
(理由給結論的支持未達足夠有效的程度)
E.g. The girls in my class are weak in critical thinking. Probably all girls are weak in
critical thinking.
Practice:
Are these arguments? If these are arguments, are there any fallacies?
1.
I buy these pills because the superstar Joey says that it helps prevent H7N9
influenza.
(a)  An argument
 Not an argument
(b)  Committed the fallacy of
 No fallacy  Not applicable
irrelevance
______________________________
(c) Explanation:
Joey is not a medical expert. Her opinion is irrelevant to the
effectiveness of the pills.


2.
Are you bored with the speeches given by those politicians? Then vote for me/
Don’t forget, vote for me, David Chan.

(a)  An argument
 Not an argument
(b)  Committed the fallacy of
 No fallacy  Not applicable
______________________________
(c) Explanation:
This is not an argument, because the sentence just expresses an appeal and has
neither a reason nor a conclusion.

S.3 /Liberal Studies (2014-2015) / Critical Thinking P.12
3.
We do not allow teenagers under the age of 18 to drink alcohol because they are
too young.
(a)  An argument
 Not an argument
(b)  Committed the fallacy of
 No fallacy  Not applicable
inappropriate presumption /
______________________________
insufficency
(c) Explanation:
The statement assumes that age under 18 is young and young people should not
drink. However, it does not explain why young people should not drink.OR
This is an empty statement. The reason does not support the conclusion and


OR

merely repeats the conclusion. /
The reason that they are too young is insufficient. There should be more
explanations like people under the age of 18 cannot have good self- control or
their internal organs are not fully developed to cope with the problems caused by
alcohol.
4.
The government should spend less on education, otherwise Hong Kong people
will not be able to enjoy medical improvement
(a)  An argument
 Not an argument
(b)  Committed the fallacy of
 No fallacy  Not applicable
inappropriate
presumption
______________________________


(c) Explanation:
This argument is based on the assumption that the government can only choose
between spending money on either education or medical improvement. People
are distracted from the fact that there may be other alternatives e.g. spend more
on both education and medical improvement and less on something else.
5.
I met some students from Tanghin yesterday, who were very polite. I think all
students from that school must be well-behaved.
(a)  An argument
 Not an argument
(b)  Committed the fallacy of
 No fallacy  Not applicable
insufficiency
______________________________


(c) Explanation:
The students he met yesterday may not be sufficient to represent all students in
Tanghin. This is over-generalisation.
6. One thing that we know for certain is that nothing is ever true or false.
(a)  An argument
 Not an argument

Inconsistency

S.3 /Liberal Studies (2014-2015) / Critical Thinking P.13
(b)  Committed the fallacy of
 No fallacy
 Not applicable
______________________________
(c) Explanation:
If there is something we know for certain, then there is at least one truth that we
know. So it can't be the case that nothing is true or false.

inconsistency
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.14
6. Decide whether to accept, reject or suspend judgment on the
argument
When we are asked to solve a problem, comment an opinion or discuss an issue, we
should not make our judgment too early. We can only make sensible and rational
judgment after careful analysis and evaluation. Step 1 to 4 is a process of analysis and
evaluation.
A.
Summary
issue
Step 1: Identify the ________,
conclusion and the
the _______________
reasons supporting the
_________________________
conclusion.
_________________________.
Checkpoint: What is an issue?
What is an argument?
Step 2: Clarify the meaning of
the wordings in the argument.
Checkpoint: What are linguistic
If the context is not an issue or
contains no argument, it is
meaningless evaluate its
credibility.
E.g. The moonlight tonight is as
gentle as you.
This is just an expression of
emotion. It is meaningless to
say whether the statement is
right or wrong.
pitfalls? How many types of linguistic
pitfalls have you learnt?
credibility
Step
3: Evaluate the
____________________ of the
argument.
If some of the keywords cannot
be suspend
clarified,our
wejudgment,
should _______
_________________________.
E.g. Hong Kong people are
impolite.
Checkpoint: How many types of
arguments have you learnt? How
should we evaluate the arguments?
Step 4: Identify any logical
fallacies have you learnt? Can you
Step 5: Decide whether to
accept
reject
_____________,
___________
suspend
or _______________________
give some examples for each type?
on the argument.
fallacies in the argument.
Checkpoint: How many types of
You may choose to accept, reject or suspend judgment at any point in the process of
critical thinking. Critical thinking is a process of analysis and evaluation. We can
only make sensible and rational judgment after careful analysis and evaluation.
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.15
7. Writing counterarguments
Counterargument refers to the one or several additional argument(s) used to refute
the reason(s) that support the conclusion, so that the readers understand certain
opposite opinions. In the argument process, we sometimes deliberately add in some
counterarguments, not for overturning the original arguments, but to let our readers
understand that we have comprehensively considered some opposite arguments and
opinions.
Example:
Rock-climbing is good for the personal development of young people.
Some people say that rock-climbing looks rather dangerous. Young people
may not have enough skill and safety awareness when they go rock climbing. They
may injure themselves easily.
However, I do not agree with the above view. Rock climbing can also be safe.
If the apparatus are carefully checked and protective measures are taken, one can
enjoy the fun of it without worrying about its safety.
Also, Rock-climbing is challenging and builds self confidence as well as
improving one’s physique. It is a good way for young people to improve their
personal development.
Is rock-climbing good for the personal development of young people?
(a) What is the issue? ___________________________________________________
yes
(b) Does the writer support rock-climbing? __________________________________
(c) What are his arguments?
Argument 1:
Conclusion:
Rock climbing can also be safe
Reasons
If the apparatus are carefully checked and protective measures are
taken, one can enjoy the fun of it without worrying about its safety.
Argument 2:
Conclusion:
Reasons
It is a good way for young people to improve their personal
development.
Rock-climbing is challenging and builds self confidence as well as
improving one’s physique.
(d) What is his counterargument?
Conclusion:
Rock-climbing looks rather dangerous.
Reasons
Young people may not have enough skill and safety awareness
when they go rock climbing. They may injure themselves easily.
(e) Why should we add in a counterargument?
Let our readers understand that we have comprehensively considered some
_____________________________________________________________________
opposite arguments and opinions.
_____________________________________________________________________
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.16
Practice:
1. Do you agree with the following statement? Please provide at least 2 arguments
and 1 counterargument.
“The government should guarantee that local kids get places of kindergartens
in their own district.”
Agree points:
- Local families have contributed to
Hong Kong society, such as paying
tax and working in Hong Kong.
- Local students have the right to
education in the nearby district.
- It is time consuming for local
students to study in other district and
affects their learning and health.
- Even though mainland students have
a lower priority in getting places in
the kindergartens in North District, it
does not violate their right to
education as they can still apply
kindergartens in all other districts.
Counterargument: Some people say that
Reasons:
Argument 1: Conclusion: However,
Reasons supporting your conclusion:
Argument 2: Conclusion:
Reasons supporting your conclusion:
Disagree points:
- The students from mainland are also
Hong Kong citizens. They should
have the same rights for Hong Kong
residents.
- The travelling time for the mainland
students is longer than that for local
students. Therefore the policy may
also affect their learning and health.
- The criteria of getting into a
kindergarten should depend on the
abilities of students, not where they
live.
S.3 /Liberal Studies (2014-2015) / Critical Thinking P.17
FURTHER READINGS
1.
2.
3.
4.
5.
《批判思考》
。香港：齡記出版社。
思方網 http://philosophy.hku.hk/think/chi/ (中)
李天命著：
《語理分析的思考方法》
。香港：青年書屋，1981 年。
李天命著：
《李天命的思考藝術》(終定本)。香港：明報出版社，1995 年。
李天命著：
《哲道行者》
。香港：明報出版社，2005 年。
GLOSSARY
1.
Critical thinking
批判思考
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Issue
Argument
Reason
Reason indicator
Conclusion
Conclusion indicator
Linguistic pitfall
Obscurity
Incomplete meaning
Vagueness
議題
論述
理由
理由指示符
結論
結論指示符
語言陷阱
語意不清
闕義
含混
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
Distortion
Empty content
Credibility
Deductive argument
Inductive argument
Validity
Soundness
Strength
Logical fallacy
Fallacy of inconsistency
概念扭曲
言辭空廢
可信度
演繹論證
歸納論證
對確度
對當度
強度
邏輯謬誤
不一致
22.
23.
24.
25.
26.
Fallacy of inappropriate presumption
Fallacy of irrelevance
Fallacy of insufficiency
Suspend judgment
Analyze
不當預設
不相干
不充分
暫緩作出判斷
分析
評估
用來反駁的論點
27. Evaluate
28. Counterargument