Lecture # 1
Fundamental Concepts in
Logical Thinking and
Reasoning
Instructor: Sumera Kazi
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1. Logic and its terms
2. Introduction to Arguments
Getting
started with
Logical
Reasoning
3. Introduction to Conclusions
4. Introduction to Questions Catalog
5. Introduction to Evidences
6. Introduction to Flaws
7. Anatomy of a Logical Reasoning Question
8. Practice Questions
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 Definition: Logic is the systematic study of valid
rules of reasoning to conclusion, more broadly,
logic is the examination and judgment of
arguments.
Logic & Its
Terms
 Terms:
1.
2.
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6.
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Arguments
Conclusion
Justification
Reasoning
Assumptions
Inferences
Fallacy
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 2 Rules of Good/Sound Argument
 Rule 1: Reason must be true
 Rule 2: Conclusion must follow a process of reasoning
 Elements
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Argument
 Claim (True/False: St of argument you hope to prove)
 Ground (Is there any evidence to support the claim?)
 Warrant (Connection between claim & ground, does ground justify
the claim)
 Types
 Deductive (from general premise to specific premise)
 "All bald men are grandfathers. Harold is bald. Therefore, Harold is a
grandfather,"
 Inductive (from specific premise to general premise)
 "Harold is a grandfather. Harold is bald. Therefore, all grandfathers are
bald.“
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 A conclusion is a statement that has been reached by a process of
reasoning.
 Examples: This job description is inadequate because it is too vague. It
doesn't even list the specific tasks that should be performed, and it doesn't
say how my performance will be evaluated.
 keywords of a conclusion sentence or a conclusion clause;
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Conclusion
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Thus
Therefore
Hence
So
Conclude
It follows that
As a result
Clearly
Obviously
Nevertheless
Nonetheless
 Warning! If not these conclusion words, then;
 The cat will run away if you open the door. That's because the cat doesn't
like being inside.
 The basics
 Support: A claim that acts as evidence for another claim.
Conclusion: A claim that is backed by support.
Background: A statement that provides contextual information but
doesn’t play a role in the argument.
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 Justification
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Justification
 Not sure about certainty of the claim, then
justification/warrant helps in proving that claim.
 For example, a crime has been committed. The victim (we’ll
call her Vera) claims that her neighbor (Nick) was the one who
did it, perhaps because she doesn’t like him, or perhaps
because she wants to see someone convicted, and anyone
will do. Other than this she has no reason for making the
allegation, and certainly nothing that would count as
evidence. But then suppose it is discovered that Nick, just as
Vera has claimed, is guilty of the crime! Would the discovery
of Nick’s guilt justify Vera’s accusation? No. It would just be
chance that the claim she had made was true. Given her
motives her claim would still be a lie. Weak Justification.
 Pertaining same situation, if there were CCTV coverage and
Nick was caught on Camera: Strong Justification.
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 Example 1
 CLAIM: War is not stopped by technological progress.
 GROUND: Inventions of gunpowder, nuclear weapons.
 WARRANT: Technological progress is driven by war; in fact,
technology tend to make war more destructive.
 Example 2
Examples
 CLAIM: Historians and social scientists can prevent poverty through
economic policy.
 GROUND: New deals, social security.
 WARRANT: Social programs prevent poverty.
 Example 3
 CLAIM: Student are using e-books more as compared to paper
books.
 GROUND: Free downloading access, readily available.
 WARRANT: Students learn more readily from electronic media than
they learn from print media.
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 Mental thinking process looking for reasons to
beliefs, conclusions, feelings and actions.
 Examples:
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Reasoning
 You are late because your car ran out of gas.
 I have to pay late fees as I was out of the station.
 Sara is the best athlete in the province. After all, she
has won medals in 8 different Olympic sports.
 The reason he was climbing the mountain so quickly
is that he is a professional hiker.
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An Assumption is an unspoken idea on
which a statement rests.
Something that we think is true.
Examples:
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Assumption
 I don’t like people who continually interrupt
me; therefore, I don’t like Javed:
 Assumed: Javed continually interrupts the
author.
 We assume that if we follow proper SOPs in
this COVID-19, we will be saved from it.
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 When we arrive at a new belief on the basis of
reasons, we are said to draw an inference.
 Pull from
 Examples:
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Inferences
 80% of the people in a carefully conducted poll are
going to vote for Islamic Party.
 Inferred: The Islamic Party will win.
 Only a minority of children under the age of 6 have
visited a dentist.
 Inferred: A majority of children under the age of 6 have
not visited a dentist.
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Fallacy
 Flawed lines of reasoning
 An error in reasoning that invalidate the
argument.
 A mistaken belief, esp. based on unsound
argument.
 Examples:
 Titanic was unsinkable, said by people in 1912.
 We should ban the hairspray or else the world
will end.
 Tigers and lions are ruthless killers so house
cats must also be ruthless killers.
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