© EDB; D.Halpern, K. Ku, I. Ho, KT Hau 1 Fundamentals of Critical Thinking.

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Fundamentals of Critical Thinking

Do You Agree?Simon says, “If I catch a cold, I will take sick leave from school. I

take sick leave from school today, therefore I must have a cold.”Peter says, “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.”

Wylie says, “Tim’s decision must be sensible because he never makes stupid decision.”

Caroline says, “The weather is getting cold because the temperature is dropping.”

Is There a Problem With What They Say?

Why Do We Need Critical Thinking?

Overwhelming InformationWe need to reorganise and make sense of the overwhelming

information we encounter in daily life

Consumer SocietyTV, Radio and other media often try to persuade us to believe in certain

things and to make insensible purchases

Decision-makingStudents are faced with many important decisions which may have an

impact on their future

Problem-solvingEmployers often expect knowledgeable employees with problem-solving

ability

Course Content

Argument Analysis• Distinguish between strong and weak arguments• Assumptions• Invalid Arguments

Evaluating Causal Claims• Understanding two related events do not

necessarily make a cause and effect relationship• Understanding common fallacies

Understanding Mental Models

Avoiding being influenced by your own biases

Employing decision-making tools to make reliable decision

Course Content

Our Goals:

• Pay special attention to your thinking processes

• Be critical about information from different media such as TV, radio and magazines

• Think carefully when faced with persuasion

Who is using critical thinking in the following scenarios?

Jennifer had a problem. She had to attend a college entrance exam the next day. Her best friend Sandra invited her to attend a farewell party that night because Sandra was going to study abroad soon. Jennifer knew that her exam performance would be affected if she went to the party. However, she did not want to miss the gathering and upset her friend, and thus accepted the invitation.

Scenario 1

Anki needed to reduce her weight to join the dancing group. The aunt of her friend had successfully reduced 20 pounds after taking some diet pills. Anki found that the pills contained a considerable amount of caffeine. She decided to consult with her coach. Her coach arranged for her to meet with a nutritionist for a diet menu that was suitable for her. Anki considered the latter methods as more applicable.

Scenario 2

In the Context of Critical Thinking

Argument is not the same as disagreement

An argument is a set of statements comprised of at least one conclusion and one supporting reason

Point of View (based on opinions):• Based on personal preferences and/or opinions• Not based on reasons

Reason:• Supporting the point of view• A reason can be a fact or a theory

Argument:• The process where reasons are used to

demonstrate the point of view• An argument must comprise at least one reason

and one conclusion

Point of View, Reason and Argument

Argument

The Structure of an Argument

• Reason

• Conclusion

• Assumption

Reason

Conclusion

Argument

(Assumption)

“You should sleep early tonight because a good sleep will help tomorrow’s exam .”“Because of cheating, Ben was disqualified from his Chinese exam.”“It’s cold in the classroom.” “Dr Chan reminds us that a balanced diet and regular exercises help to keep us healthy.”“You should buy this jacket.”

Arguments and Non-arguments Arguments and Non-arguments

Which of the above are arguments and which are not?

You Will Also Practise

How To…

Distinguish Among…

ReasonAssumption

Conclusion

We often use indicators to help stating an argument

An indicator is used to emphasise a reason or conclusion to be put forward:

“The sun is out, so it won’t rain.”

Can you identify the indicator in the above

sentence?

Commonly Used Reason Indicators:

“Since unexpected events may happen during travel, you should take out travel insurance.”

•Because, since, seeing that, etc.•The reasons include…•First of all, to begin with, in the first place, etc.• It can be seen that…, It has been shown that …from…, etc.

•On account of, on the basis of, because of, etc.

Commonly Used Conclusion Indicators:• So, therefore, hence, thus, etc.• As a result, as a consequence, etc.• Based on these grounds• This shows/suggests/indicates…• In a word, in sum, in short, in brief• We can sum up

“The sun is out, so it won’t rain.”

Reason

Strong, Weak or Irrelevant Reasons

There are reasons that fully support the conclusion, reasons that barely support the conclusion, and reasons that are irrelevant to and thus do not support the conclusion.

•Strong

•Weak

•Irrelevant

Reason

Strong Reasons

Example:

“The weather forecast says it is going to rain soon, so you should not go barbecue.”

A strong reason must be reasonable in the first place, and it should be supported by truth, fact or theory that can be proved.

Weak Reasons

A weak reason cannot rule out other possible factors that may lead to the same conclusion.

Example:“This shop should be moved to another shopping arcade. It is because it rained in the last few days and the turnover was really unsatisfactory .”

Irrelevant ReasonsIrrelevant reasons refer to those reasons that are logical fallacies or do not give any support to the conclusion.

Example:“It is sunny today, therefore the chief executive of Hong Kong should buy a new tie.”

Assumption in Argument

Assumption:

When stating a reason, we often omit the underlying assumption. Even when we mention the assumption, we tend not to give a detailed explanation about it.

Example:

“The video game centre must be closed during class hours because students are skipping classes.”

What are the Assumptions in the Above Sentence?

1) The statement assumes that by closing the video game centre is closed, no other factors will cause students to skip classes.

2) The statement implies that students skip classes to go to the video game centre.

What Might Have Been Omitted in the Above Example?

• We have no idea whether those who skip classes have actually gone to the video game

centre or somewhere else.

When evaluating arguments, we need to take into consideration the omitted assumptions.

What is a Counterargument?

• When we disagree with or question other’s point of view, we may put forward a counterargument to challenge his/her point of view

• A counterargument may just serve to provide another perspective

Example 2:Investors should be cautious about the stock market, (Conclusion)as it on one hand has promoted the growth of the economy, (Counterargument)on the other has led to blind investments of people and people lose their jobs, resulting in severe financial loss. (Reason)

Example 1:The government should support generating electricity by nuclear energy. (Conclusion)Although the use of nuclear energy in generating electricity may bring about the problem of nuclear waste, (Counterargument)yet such energy has reduced air pollution and greenhouse effect caused by using coal. (Reason)

Example 3:The government should support online business. (Conclusion)Although both buyers and sellers may need to bear certain risks for their transaction because of the lack of government supervision, (Counterargument)it is highly efficient which benefits both parties. (Reason)

Example 4:Although we are still not clear about the possible long-term side effects of genetically modified products on our health, (Counterargument)such products are of lower cost and better quality. (Reason)Therefore, we should not ignore such a technology that brings us great benefits and convenience. (Conclusion)

Fallacies

Two Common Fallacies:

• Affirming the Consequent

• Circular Reasoning

Affirming the Consequent

• If A, then B; Now B, we assume A is true.

If I catch a cold, I will take a sick leave from school.• Now I take a sick leave from school,• I must have a cold.

If there is a lack of government assistance, life will be difficult for farmers.

• Now the farmers find life difficult,• There must be a lack of government assistance.

Circular Reasoning• The premise is simply a restatement of the conclusion.• Assuming that the conclusion is true in the premises does not constitute evidence for that

conclusion.

His decision must be sensible because he never makes stupid decision.

The weather is getting colder because the temperature is dropping.

Keep the Following Points in Mind

• An argument must contain at least one reason and one conclusion.

• When stating an argument, assumptions are often omitted and hidden in the sentence.

• We must carefully evaluate the strengths of the reasons.

• An argument should be based on strong and supportive reasons.

Critical thinking takes effort…

Bear in mind to cultivate the habit of careful thinking!

But you will

benefit from it.

© EDB; D.Halpern, K. Ku, I. Ho, KT Hau 1 Fundamentals of Critical Thinking.

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