This document provides an introduction to critical thinking. It defines critical thinking as the ability to think clearly and rationally about what to believe or do. It discusses attributes of critical thinkers such as being rational, open-minded, and not taking things for granted. The document also outlines different types of reasoning including deductive, inductive, and abductive reasoning and how to practice critical thinking by carefully evaluating arguments and checking the validity of facts. It emphasizes the importance of distinguishing facts from opinions and providing evidence to support opinions.
2. Agenda
• What is critical thinking?
• How to practice critical thinking?
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3. What is critical thinking?
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4. What is critical thinking?
• Critical thinking is the ability to think
clearly and rationally about what to do
or what to believe.
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5. What is not critical thinking?
• Mere criticize everything
• Thinking a lot
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6. What hinder critical thinking
• Lack of awareness/practice of rational
(logical) thinking
• Personal biasness
• Cultural biasness
• Intellectual arrogance
• Intellectual laziness
• Black & white thinking
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7. Attribute of critical thinkers
• Rational
• Think extra yard than others
• Demand reasoning
• Open minded
• Ask right questions
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8. Attribute of critical thinkers (con.)
• Do not take anything for granted
• Do not jump into conclusions
• Do not fear challenging
politically/culturally dominant views
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9. How to practice critical
thinking?
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10. How to do critical thinking?
1. Do careful, intentional thinking
o Fully evaluate all parts of argument/claim
2. Analyze & evaluate each piece of the
argument
o Identify facts and opinions
o Evaluate the opinions
3. Use of reason or logic to check the validity
4. Check truthfulness of each fact to see if it is a
sound argument
5. Application/test with real world scenarios to
verify
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11. Fact vs. Opinion
Fact
• A statement of fact can be proved TRUE
or FALSE using standard knowledge
o An observable or obvious thing
o It has been proved by scientific experimentation
o Can be deduced by formal logic
• Example
o Earth is round
o Smoking causes cancer
o There is a force towards the earth
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12. Fact vs. Opinion
Opinion
• A statement of opinion is what someone
believes or thinks
o He must provide enough evidence to prove his opinion
• Called burden of proof
o We have to test if that opinion is valid or not
o If we do not accept the opinion we must show the fault in the
opinion
• We do not have to prove that opinion is false
o We may or may not provide alternative opinion
• Example
o There is life after death
o Mr. X is a better leader than Mr. Y
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13. Problem solving techniques
• Deductive Reasoning
o Best approach
• Inductive Reasoning
o There are situations to be used
o Use with care
• Abductive Reasoning
o Wrong approach
o Use with care
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15. Deductive Reasoning
• Derive logically necessary conclusion
from given premises/ assumptions
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16. How to come to judgements?
• Using formal logic
o Example:
X > 4
y > x
Therefore y >4
• Using scientific knowledge
o Example
• Removing oxygen will extinguish fire
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17. What is an argument?
• An argument is set of assumptions/
premises followed by a conclusion
• Example:
Socrates is a philosopher. (Assumption)
All philosophers like thinking. (Assumption)
Therefore Socrates likes thinking. (Conclusion)
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18. Outcome of an argument
Argument
Invalid
Valid
Sound
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19. What is a valid argument?
• An argument is said to be valid if the
conclusion is logically true, whenever all
the assumptions/premises are true
• Example
o Valid argument
If there is an earthquake, the detector will send a
message.
No message has been sent.
So there was no earthquake.
o Invalid argument
Whenever Anil is here, Kumar is also here.
Anil is not here.
So Kumar is not here.
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20. What is sound argument?
• If an argument is valid and all the
assumptions are found/proved to be
correct, then the argument is said to
be sound.
• We must accept only the sound
arguments!
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22. Inductive Reasoning
• Use patterns of concrete instances to
arrive at a conclusion
• It’s a way of generalization through
observation and careful systematic
analysis
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23. How to come to judgements?
• By analyzing results of empirical data
using concepts of statistics and
probability
o Example:
Is the value considerably higher than average for a
sample with particular feature
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24. Inductive Reasoning - caution
• Use of smaller sample may lead to
false conclusion
• What is your visibility may be too
narrow
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25. Inductive Reasoning - caution
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What you have seen
is not close to reality
in general.
27. Abductive Reasoning
• Abductive reasoning allows inferring a as an
explanation of b
• As a result, abduction allows the precondition a
to be adduced from the consequence b (i.e.
effect to cause)
• Deductive reasoning and abductive reasoning
thus differ in the direction in which a rule like " a
entails b is used for inference.
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Incomplete
observation
Best prediction
(May be true)
28. Abadductive Reasoning - caution
• Considerable risk of inferring wrong
cause
• You may infer A as the cause, whereas
actual cause might be C in this case
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A
B
C
D
.
.
P
Q
R
.
.
29. Overview of reasoning
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General
rule
Specific conclusion
(Always true)
Specific
observation
General conclusion
(May be true)
Incomplete
observation
Best prediction
(May be true)
Deductive Reasoning
Inductive Reasoning
Abductive Reasoning
