This document discusses inductive arguments. It defines inductive arguments as those whose premises provide evidence for but do not guarantee the conclusion. It then examines 4 types of inductive arguments: enumerative induction, statistical syllogism, causal argument, and analogy. It provides examples of each type and criteria for evaluating the reliability and strength of inductive arguments.
“A syllogism is a kind of logical argument that applies deductive reasoning to arrive at a conclusion based on two or more propositions that are asserted or assumed to be true.” Wikipedia contributors. "Syllogism." Wikipedia, The Free Encyclopedia. 7 Jun. 2015. Web. 14 Jun. 2015
“A syllogism is a kind of logical argument that applies deductive reasoning to arrive at a conclusion based on two or more propositions that are asserted or assumed to be true.” Wikipedia contributors. "Syllogism." Wikipedia, The Free Encyclopedia. 7 Jun. 2015. Web. 14 Jun. 2015
Logic is derived from the Greek word ‘LOGOS’ which means primarily the word by which the inward thought is expresses ‘LOGIKE’ which means the work or what is spoken (but coming to mean thought or reason).
Credited to Math 2A.
Logic is derived from the Greek word ‘LOGOS’ which means primarily the word by which the inward thought is expresses ‘LOGIKE’ which means the work or what is spoken (but coming to mean thought or reason).
Credited to Math 2A.
Question 1 Evaluate a mode of study that you do well and one.docxIRESH3
Question 1
Evaluate a mode of study that you do well and one that you could improve on. Please explain
how you plan on improving that which you find to be weak in your own study habits.
Your response should be at least 75 words in length. You are required to use at least the attached
textbook as source material for your response. All sources used, including the textbook, must be
referenced; paraphrased and quoted material must have accompanying citations.
Question 2
Describe the two ways that students normally study in a typical college course.
Your response should be at least 75 words in length. You are required to use at least the attached
textbook as source material for your response. All sources used, including the textbook, must be
referenced; paraphrased and quoted material must have accompanying citations.
Question 3
Describe the typical design of a college course and the outcomes that result for students in these
courses. In addition, describe a situation in which you found yourself falling into this style of
learning.
Your response should be at least 200 words in length. You are required to use at least the
attached textbook as source material for your response. All sources used, including the textbook,
must be referenced; paraphrased and quoted material must have accompanying citations.
Course Learning Outcomes for Unit V
Upon completion of this unit, students should be able to:
1. Display competence in the art of analyzing the logic of the subject one is studying.
2. Determine the purpose of analyzing the logic of the subject one is studying.
3. Compare and contrast the logic of college as it is and as it should be.
4. Assess the logic of the four modalities of communication.
5. Appraise the criteria for evaluating an author's reasoning by using the elements of thought.
6. Identify how one should assess one's progress in learning.
7. Describe the strategies for self-assessment.
8. Apply the generic model to various applied majors
Unit Lesson
This lecture continues with the discussion of rhetorical devices.
Downplayers
A downplayer is a word that is inserted in a sentence that undermines something that is being discussed. Let’s take a look at two
sentences that mean the same thing in their deepest structure, but that have radically different connotations due to one word.
“Brent got a B on his exam.”
“Brent only got a B on his exam.”
By inserting the word “only,” the person saying sentence two has downplayed Brent’s achievement. Most people would be
happy, or at least satisfied, with a grade of B on an exam. However, the second sentence seems to diminish Brent’s
accomplishment by indicating that a grade of B on the exam does not meet his or her expectations of Brent. You can think of
downplayers as using scare quotes “” in verbal language. Let’s look at some more examples.
“Yeah, Ellen just got her ‘degree’,”
In this case, the person seems to indicate ...
Statistical arguments are found in many aspects of our daily liv.docxdessiechisomjj4
Statistical arguments are found in many aspects of our daily lives for example sports fans, doctors, scientists, etc.
A personal example I have for statistical syllogism arguments is the following:
90% of Joe’s biological family has high blood pressure.
Kayla is Joe’s biological daughter.
Therefore, Kayla has a 90% chance of having high blood pressure.
I feel this is a strong inference for a statistical syllogism argument because family medical histories can be documented as well as blood pressure being taken or monitored. According to the textbook the example of:
X% of S are P.
I is an S.
Therefore, I is (probably) a P.
Inductive Generalizations are an argument that information is taken from a trial period of testing.
25% to 35% of your total daily calories should be good fats from fish, nuts, and vegetable oils.
Therefore, 25% to 35% of good fats are from fish, nuts, and vegetable oils.
(Know Your Fats, 2014).
This I feel is a strong argument because the American Heart Association is an authority on fat guidelines for healthy Americans. A sample testing form according to the texts looks like this:
X% of observed Fs are Gs.
Therefore, X% of all Fs are Gs.
Finally a Random Sample which gives a population of a location.
Almost everyone at the Vending Warehouse cleans their shoes before walking on the new carpet.
The receptionist reminds the movers to clean their shoes before walking on the new carpet.
Therefore, almost everyone at the Vending Warehouse cleans their shoes before walking on the new carpet.
I work in a Vending Warehouse and I constantly have to remind the Movers to clean their shoes. It is a pretty strong argument because there are camera’s everywhere.
References:
(April 21, 2014). Know Your Fats. American Heart Association. Retrieved from http://www.heart.org/HEARTORG/Conditions/Cholesterol/PreventionTreatmentofHighCholesterol/Know-Your-Fats_UCM_305628_Article.jsp#.VkvSItGFNMs.
Hardy, J., Foster, C., & Zúñiga y Postigo, G. (2015). With Good Reason: A Guide to Critical Thinking [Electronic version]. Retrieved from https://content.ashford.edu/
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5Inductive Reasoning
Iakov Kalinin/iStock/Thinkstock
Learning Objectives
After reading this chapter, you should be able to:
1. Define key terms and concepts in inductive logic, including strength and cogency.
2. Differentiate between strong inductive arguments and weak inductive arguments.
3. Identify general methods for strengthening inductive arguments.
4. Identify statistical syllogisms and describe how they can be strong or weak.
5. Evaluate the strength of inductive generalizations.
6. Differentiate between causal and correlational relationships and describe various
types of causes.
7. Use Mill’s methods to evaluate causal arguments.
8. Recognize arguments from authority and evaluate their quality.
9. Identify key features of arguments from analogy and use them to evaluate the strength of
such arguments.
har85668_05_c05_165-206.indd 165 4/9/15 11.
Week 3 - Instructor Guidance
Week 3: Inductive Reasoning
This week’s guidance will cover the following topics:
1. The Nature of Inductive Reasoning
2. Appeals to Authority
3. Inductive Generalizations
4. Statistical Syllogisms
5. Arguments from Analogy
6. Inferences to the Best Explanation
7. Causal Reasoning
8. Things to Do This Week
The Nature of Inductive Reasoning
Will the sun rise tomorrow morning? Of course it will, but how do you know? The reasoning seems to go as follows:
Premise 1: The sun has risen every morning throughout known history
Conclusion: Therefore, the sun will rise tomorrow
Deductively, this argument is invalid, for it is logically possible that the earth could stop spinning tonight. Does that mean that the argument is no good? Of course not. In fact, its premise makes the conclusion is virtually certain. This is an example of a very good argument that is not intended to be deductively valid. That is because it is actually an inductive argument.
An argument is inductive if it does not attempt to be valid, but intends to give strong evidence for the truth of its conclusion.
Many might see inductive reasoning as inferior to deductive reasoning, but that is not generally the case. In fact, inductive arguments often provide much better arguments for the truths of their conclusions than deductive ones. The deductively valid version of our argument about the sun, for example, goes:
Premise 1: The sun will always rise in the morning
Conclusion: Therefore the sun will rise tomorrow morning
This second argument, while valid, actually gives less evidence for the conclusion because its second premise is false (the sun will eventually expand to engulf the earth and then collapse). Therefore the deductive argument is unsound and so offers little evidence for the conclusion, whereas the original inductive argument made the conclusion virtually certain. In other words, inductive reasoning in general can be even better than deductive reasoning in many cases; the trick is to determine which inductive arguments are good and which ones are not so good.Strength versus Weakness
Just as it is the goal of deductive reasoning to be valid, it is the goal of a inductive reasoning to be
strong
. An inductive argument is strong in case its premises, if true, would make the conclusion very likely to be true as well. The above argument about the sun rising is very strong. Most inductive arguments are less strong, all the way along a spectrum between strength and weakness. Here are three with varying degrees of inductive strength:
Weak:
Premise 1: John is tall and in college.
Conclusion: Therefore, he probably plays on the basketball team.
Moderate:
Premise 1: The Lions are a 14 point favorite.
Conclusion: So they will probably win.
Strong:
Premise 1: All of the TV meteorologists report a 99% chance of rain tomorrow.
Conclusion: So it will probably rain tomorrow.
Note that the degree of strength of an inductive argument is independent of whether the.
2. Let’s review what an inductive
argument is.
Any argument whose premises may provide evidence for
its conclusion or hypothesis but do not guarantee it.
Here’s an example of an inductive argument:
1. Pam is athletic.
2. Most of those who are athletic don’t eat junk food.
_____________________________________________________________________________________________________________
3. Pam doesn’t eat junk food.
3. To determine whether an argument
is inductive, consider:
• whether it would be possible for an argument
with the same form to have true premises and
a false conclusion
• whether one can assert its premises and deny
its conclusion without contradiction
• whether the conclusion adds information not
contained in the premises
5. Enumerative Induction
Always has a universal conclusion to the effect
that all things of a certain kind have (or lack) a
certain feature. This conclusion is drawn from
evidence that some things of that kind have (or
lack) that feature.
The conclusion of this type of argument, often
called an inductive generalization, is a universal
generalization.
6. Enumerative induction attempts to support universal
generalizations by using non-universal generalizations
or specific statement as premises.
1. Many roses have been observed to blossom in the summer.
_______________________________________________________________________________________________
2. All roses blossom in the summer.
--or--
1. Rose 1 has been observed to blossom in the summer.
2. Rose 2 has been observed to blossom in the summer.
3. Rose 3 has been observed to blossom in the summer. . .
4. Rose number n, has been observed to blossom in the summer.
__________________________________________________________________________________________________________
5. All roses blossom in the summer.
7. So what’s a universal generalization?
A statement asserting that all of the members of a certain
class have (or don’t have) a certain feature.
May be expressed by a great number of different patterns
of sentence.
Some standard patterns:
• “all . . . are”
• “every . . . is”
• “no . . . is”
8. Non-Universal Generalization
A statement asserting that some, perhaps many, of the
members of a class have (or don’t have) a certain
feature.
May be expressed by a great number of different
patterns of sentence. Some standard patterns:
• “most . . . are”
• “a few . . . are”
• “many . . . are”
• “n percent of . . . are” (where n is less than 100%)
• “some . . . are”
• “some . . . are not”
9. Statistical Syllogism
A statistical syllogism is an inductive argument
whereby a certain feature is ascribed to a case or
cases on the basis of their being subsumed within
a larger class of things, some of which, perhaps
many, have the ascribed feature.
1. Most surgeons carry malpractice insurance.
2. Dr. Hagopian is a surgeon.
________________________________________________________________________________________________________________
3. Dr. Hagopian carries malpractice insurance.
10. Causal Argument
According to the textbook, a causal argument
makes the claim that two or more things or
events are causally related in either of these
ways:
• Effect E results from cause C.
• C causes E.
• E and C are the cause or the effect of another
thing X.
12. Examples of Causal Arguments
• HIV causes AIDS.
• Having the genome of a cat causes Fluffy
the kitten to grow up to be a cat.
13. Three Meanings of Cause
• Sufficient Cause: C is a sufficient cause of E
if, and only if, C always produces E.
• Necessary Cause: C is a necessary cause of
E if, and only if, E cannot occur in the
absence of C.
• Necessary and Sufficient Cause: C is a
necessary and sufficient cause of E if, and
only if, C always is the sole cause of E.
14. Analogy
Analogy is a type of inductive argument whereby a
certain conclusion about individuals, qualities, or
classes is drawn on the basis of some similarities with
other individuals, qualities, or classes.
Whether an analogy succeeds depends on:
• the number of things and the number of features held to be
analogous
• the degree of similarity or dissimilarity among those things
• the relevance of ascribed features to the hypothesis
• the boldness of the hypothesis with respect to the evidence
15. Here’s an example of an Analogical
Argument:
This is the argument’s form:
16. Criteria for Inductive Argument
Evaluation
Reliability
Concerns argument form and is, in this respect, comparable
to validity for deductive arguments.
In a reliable argument, the relation of premises to conclusion
is such that, if all the premises were true, it would be
reasonable to accept the conclusion.
Strength
Requires that the inductive argument be reliable and have
true premises (compare deductive soundness). When an
argument is inductively strong, it’s reasonable to accept its
conclusion.
17. The “Cash Value” of Reliability
and Strength
Inductive Reliability’s Cash Value
If an argument has a good share of reliability, then it would be
reasonable to accept its conclusion, provided that its premises are
true.
Inductive Strength’s Cash Value
If an argument has a good share of inductive strength, then it’s
reasonable to accept its conclusion, since it has a reliable form and
its premises are true.