INDUCTIVE ARGUMENTS

The aim of this tutorial is to help you learn to recognize, analyze, and evaluate inductive arguments.

Inductive arguments

Inductive arguments claim that their conclusion probably follows from the premises. As a result, inductive arguments are either stronger or weaker, rather than either true or false.

Certain words and phrases are commonly used in inductive arguments; these include probably, most likely, chances are, it is reasonable to suppose, we can expect, and it seems probable that. However, not all inductive arguments contain indicator words.

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Most Corgis make good watchdogs.My dog Mindy is a Corgi. Therefore, Mindy is probably a good watchdog.

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Three types of inductive arguments

There are three common types of inductive arguments:

Generalizations

Analogies

Causal arguments

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Generalizations

We use generalization when we draw a conclusion about a certain characteristic of a group or population based on a sample from that group.

Certain data collection processes employ inductive generalization. These include polls, surveys, and sampling techniques. Types of sampling techniques include representative samples, random samples, and self-selected samples.

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Hot or Not?

Have you ever made a generalization in your life that you later found to be false?

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Problems with generalizations

Although data collected using inductive generalization techniques may be useful and credible, it is also susceptible to problems.

These problems include: Bias in wording, such as slanted questions, push polls, and

loaded questions.

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Evaluating polls or surveys

When evaluating poll or survey data, it is important to ask questions to determine the data’s worth and accuracy.

Who conducted the poll and what was its purpose? How was the sample selected? Was it large enough? Was the sample representative of the study group? What method was used to carry out the poll? What questions were asked? Were they unbiased? What other polls have been taken on this issue? Is this poll

consistent with their findings?

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Your participation in a poll helps to provide an accurate portrayal of a specific group or

a population at large.

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Internet polls and some polls sponsored by television programs or stations, such as American Idol or CNN, may be biased or unrepresentative, since they rely on

call-ins from their viewers or subscribers.

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George Gallup

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Comparative table of heights of U.S. presidential candidates

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Evaluating inductive arguments using generalization

When evaluating generalization-based arguments, the following five criteria are useful:

Check whether the premises are true. Decide if the sample is large enough. Decide if the sample is representative. Decide if the sample is current and up-to-date. Determine whether the premises support the conclusion.

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Women serving combat duty in the United States military has been an issue of contention—but are we against (or for) it for the right reasons?

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Analogies

An analogy is based on a comparison between two or more things or events. Metaphors, a type of descriptive analogy, are common in literature. Analogies can be used on their own or as premises in arguments. Arguments using analogies are common in personal relationships, as well as in many fields such as law, religion, politics, business, science, and the military.

The success of an argument using an analogy depends on the type and extent of relevant similarities and dissimilarities between the things being compared.

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An alliance of tribes, Tecumseh argued, is like braided hair. A single strand of hair is easy to break. But several strands braided together are almost impossible to break.

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Evaluating arguments based on analogy

Knowing how to evaluate arguments using analogy is a valuable critical thinking skill.

The following strategies are useful: Identify what is being compared. List the similarities. List the dissimilarities. Compare the lists. Examine possible counter-analogies. Determine if the analogy supports the conclusion.

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The argument from design states that God must exist because the world displays purposefulness.

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“I do [say what I mean],” Alice hastily replied; “at least—at least I mean what I say—that’s the same thing, you know.”

“Not the same thing a bit!” said the Hatter. “Why, you might just as well say that ‘I see what I eat’ is the same thing as ‘I eat what I see’!”

“You might just as well say,” added the March Hare, “That ‘I like what I get’ is the same thing as ‘I get what I like’!”

“You might just as well say,” added the Dormouse, which seemed to be talking in its sleep, “That ‘I breathe when I sleep’ is the same thing as ‘I sleep when I breathe’!”

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“Your Brain on Drugs”

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The claim that AI are not conscious and lack feeling because they are not organic is based on an irrelevant dissimilarity.

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Causal arguments

A cause is an event that brings about a change or effect. In causal arguments, something is claimed as the cause of something else. Understanding cause and effect relations is a crucial component of effective critical thinking.

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Serial killer Ted Bundy blamed pornography for his crimes.

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Antonia Novello

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Correlations

When two events occur together at rates higher than probability, the relationship is called a correlation. If the incidence of one event increases when the second one increases, the relationship is called a positive correlation. A negative correlation occurs when the occurrence of one event increases as the other increases.

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The correlation between cigarettes smoked and lung cancer

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Evaluating causal arguments

Knowing how to evaluate causal arguments makes it easier for you to employ them productively.

Use the following four criteria: Determine whether the evidence for a causal relationship is

strong. Make sure the argument is free of fallacies. Decide whether the data is current and up-to-date. Make sure the conclusion does not go beyond the premises.

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When making decisions on the basis of causal arguments, such as whether to allow your children to sit close to a television, your information should be up-to-date. What

was true at one time may no longer be the case.

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Conclusions

Knowledge of inductive arguments, including generalizations, analogies, and causal arguments, is essential for us to effectively function in the world. As good critical thinkers, we must constantly identify and evaluate these types of arguments, both our own and those presented to us by others.

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Perspectives on legalizing marijuana

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