Inductive/ Deductive/ Logical Fallacy

1. MC 4: LOGIC AND
CRITICAL THINKING
Deductive, Inductive and Fallacious
Reasoning/Argument

2. An argument is deductive when its premises and conclusion
are related in such a way that the truth of the premises
guarantees the truth of the conclusion.
A relationship of deductive support holds between the
premises and conclusion of a deductive argument. In a
deductive argument, if the premises are all true, then the
conclusion must be true.
DEDUCTIVE ARGUMENT

3. In a deductive argument, if all the premises are true, the conclusion cannot be false.
DEDUCTIVE ARGUMENT
Jack is a Bachelor
He has no wife
Addition is Commutative
3 + 4 = 4 + 3

4. In a deductive argument, if all the premises are true, the conclusion cannot be false.
DEDUCTIVE ARGUMENT
Jack is a Bachelor
He has no wife
Addition is Commutative
3 + 4 = 4 + 3

5. In a deductive argument, if all the premises are true, the conclusion cannot be false.
DEDUCTIVE ARGUMENT
Either Jeb is not graduating, or he has paid his tuition bill.
But he is graduating.
He has paid his tuition bill
All whales are mammals.
All mammals are warm blooded.
All whales are warm blooded

6. DEDUCTIVE ARGUMENT

7. Based on research findings, hospital leaders determine
patients recover more quickly if they receive adequate rest.
The hospital creates a policy for quiet zones at night by
initiating no overhead paging, promoting low-speaking
voices by staff, and reducing lighting in the hallways. (See
Figure 4.2).[5] The nurse further implements this policy by
organizing care for patients that promotes periods of
uninterrupted rest at night.
This is an example of deductive thinking because the intervention is applied to all patients
regardless if they have difficulty sleeping or not.
DEDUCTIVE ARGUMENT

8. The second type of argument is inductive. In such an
argument, the premises provide a different kind of
support for the conclusion. In an inductive argument,
if the premises are all true, then probably the
conclusion is true, but it might be false. inductive
support provides good reasons but not conclusive
reasons to accept the conclusion.
INDUCTIVE ARGUMENT

9. Conclusions of inductive arguments amplify or
go beyond the information found in their
premises. Conclusions of ampliative arguments
contain new information that is not present, even
implicitly, in their premises.
Inductive arguments figure strongly in reasoning
about causes.
INDUCTIVE ARGUMENT

10. Causal arguments are among the most common inductive arguments.
INDUCTIVE ARGUMENT
That a stone will fall, that fire will burn, that the earth has
solidity, we have observed a thousand and a thousand
times; and when any new instance of this nature is
presented, we draw without hesitation the accustomed
inference.
—D. Hume, Dialogues Concerning Natural Religion
Philo, the speaker in this passage of the dialogue, does not actually state the obvious conclusion—
that in the future, stones will continue to fall, fire to burn, and the earth to be solid—but his
meaning is clear.

11. Causal arguments are among the most common inductive arguments.
INDUCTIVE ARGUMENT
In this argument, you're making an educated or
informed guess based on the information or data
that you have. It might sound right, but that
doesn't mean it is right.

12. INDUCTIVE ARGUMENT
The left-handed people I know use left-
handed scissors; therefore, all left-
handed people use left-handed
scissors.

13. INDUCTIVE ARGUMENT
In the summer, there are ducks on
our pond. Therefore, summer will
bring ducks to our pond.

14. INDUCTIVE ARGUMENT
Mary and Jim are left-handed and use left-handed
scissors.
Bill is also left-handed.
Conclusion: Bill also uses left-handed scissors.

15. INDUCTIVE ARGUMENT
Mary and Jim are left-handed and use left-handed
scissors.
Bill is also left-handed.
Conclusion: Bill also uses left-handed scissors.

16. INDUCTIVE ARGUMENT

17. INDUCTIVE ARGUMENT
A nurse assesses a patient and finds the surgical
incision site is red, warm, and tender to the touch. The
nurse recognizes these cues form a pattern of signs of
infection and creates a hypothesis that the incision has
become infected. The provider is notified of the
patient’s change in condition, and a new prescription is
received for an antibiotic.

18. Sforks should be the new standard for
silverware since they were very efficient,
therefore a lot of workers will have no job at
spoon and fork factories
WHAT KIND OF ARGUMENT IS THIS?

19. Into the third category fall the fallacies. In a fallacy, or
fallacious argument, the alleged evidence offers only very
weak support or is irrelevant to the conclusion.
FALLACIOUS ARGUMENT/ LOGICAL FALLCY

20. Appeal to Force (Ad Baculum)
FALLACIOUS ARGUMENT
This fallacy appeals to an emotion (fear) rather than to our
reasoning ability. Although a threat may be a good reason
(in the sense of serving your best interests) to do
something, it should not be confused with evidence for
the truth of a statement.

21. Appeal to Force (Ad Baculum)
FALLACIOUS ARGUMENT
HOW do you read this: “GIF”

22. Appeal to Force (Ad Baculum)
FALLACIOUS ARGUMENT
HOW do you read this: “GIF”
Language is Relative, so long as people know what you
are talking about it doesn’t matter if you pronounce GIF
with a HARD or a SOFT “g”. But if you call that it a “jif”
the teacher will fail you in his subject.

23. Appeal to Force (Ad Baculum)
FALLACIOUS ARGUMENT
Using the force of one’s AUTHORITY or
POSITION to force an opponent to
concede

24. Appeal to Force (Ad Baculum)
FALLACIOUS ARGUMENT
TREAT is not an ARGUMENT

25. Appeal to Pity (Ad Misericodiam)
FALLACIOUS ARGUMENT
This occurs when we confuse feeling sorry for
someone with evidence for the truth of an
assertion that is made by or about the person
who is to be pitied.

26. Appeal to Pity (Ad Misericodiam)
FALLACIOUS ARGUMENT
John said if Tim sign a lease he has an
obligation to pay rent. Tim doesn’t like this
and responds, My pet died last month, I just
don’t know if I can take paying the rent.

27. Sforks should be the new standard for
silverware since they were very efficient,
therefore a lot of workers will have no job at
spoon and fork factories
WHAT KIND OF LOGICAL FALLACY IS THIS?

28. Jennifer always leaves for school at 7:00
a.m. Jennifer is always on time. Jennifer
assumes, then, that if she leaves at 7:00
a.m. for school today, she will be on time.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

29. How is Deductive Argument different from
Inductive Argument?
GRADED INDIVIDUAL QUIZ @

30. The cost of goods was $1.00. The cost of labor to
manufacture the item was $0.50. The sales price of
the item was $5.00. So, the item always provides a
good profit for the stores selling it.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

31. To get a Bachelor’s degree at Utah Sate
University, a student must have 120 credits.
Sally has more than 130 credits. Therefore,
Sally has a bachelor’s degree.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

32. Feminists want to ban all pornography and punish
everyone who looks at it! But such harsh measures
are surely inappropriate, so the feminists are wrong:
porn and its fans should be left in peace.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

33. The children in that house yell loudly when they
play in their bedroom. I can hear children yelling
in that house. Therefore, the children must be
playing in their bedroom.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

34. How will you determine if it is an Inductive
Argument?
GRADED INDIVIDUAL QUIZ @

35. Red meat has iron in it, and beef is red meat.
Therefore, beef has iron in it.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

36. People have been trying for years to prove that
God does not exist. But no one has yet been
able to prove it. Therefore, God exists.
GRADED INDIVIDUAL QUIZ*
Determine what kind of argument it is:

37. Ray is a football player. All the other football
players on the high school team weigh more
than 170 pounds. Therefore, Ray must weigh
more than 170 pounds.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

38. How is Inductive Argument different from
Fallacious Argument?
GRADED INDIVIDUAL QUIZ @

39. Practically every house on South Street is
falling apart. Sherry lives on South Street.
Her house is probably falling apart.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

40. All men are mortal. Joe is a man. Therefore Joe
is mortal. If the first two statements are true,
then the conclusion must be true.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

41. The chair in the living room is red. The chair
in the dining room is red. The chair in the
bedroom is red. All the chairs in the house
are red.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

42. Elephants have cells in their bodies, and all cells
have DNA. Therefore, elephants have DNA.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

43. Bob is showing a big diamond ring to his
friend Larry. Bob has told Larry that he is
planning to marry Joan. Bob must be
surprising Joan with the diamond ring
tonight.
GRADED INDIVIDUAL QUIZ @
Determine what kind of argument it is:

44. All numbers ending in 0 or 5 are divisible by
5. The number 35 ends with a 5, so it must
be divisible by 5.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

45. How will you determine if it is Fallacious
Argument?
GRADED INDIVIDUAL QUIZ @

46. Cacti are plants, and all plants perform
photosynthesis. Therefore, cacti perform
photosynthesis.
GRADED INDIVIDUAL QUIZ
Determine what kind of argument it is:

47. Give 5 examples of each of the arguments
presented (5 for inductive, 5 for deductive, 10 for
fallacies [5 for ad misericodium and 5 ad
baculum])
A S S I G N M E N T