Rhetorical strategies

Persuasive words, Logical fallacies and Intent signals

Persuasive words

How are words used so as to get you to go along with what the speaker intends, perhaps without him or her having to really make a full case? (These do not, by themselves, mean his or her ideas don't deserve assent!!)

Anecdotes, Stories, Metaphors

These cast an issue in a favorable or unfavorable light, or can highlight or suppress certain aspects. They work by suggesting a likeness between a character and the listener, or a situation and the listener's. What is emphasized or suppressed is key.


One way of getting a child to eat her vegetables is to offer a "choice" "Would you like peas or spinach?" Regardless of the alternative chosen, your desired objective is met. "Which kind of environmental bureaucracy do you want -- one that stifles business and innovation, or one that burdens American industry with impossible extra costs?"


This works by getting you to accept both parts of a statement because of how they are linked; one part might be reasonable enough by itself, but. . .
"Unless you want the earth to turn to a barren crust, you must oppose corporate capitalist pigs, tooth and nail."


How does the author go about building a sense of friendliness and receptivity on the part of the audience? Some methods are friendly introductions ("my friends"), complimenting, showing respect, speaking the speakers 'language,' and conveying optimism. These are important communicative techniques! Rapport is important. We just have to be aware of its use in persuasive contexts.


A speaker may claim in many ways to be an authority; sometimes external checking of this is called for.


Humor has a great way of defusing our critical faculties. Not that it's bad in itself; it should just raise a red flag lest we go too far down the garden path on which someone wants to lead us.

Emotional words

Advertisers are especially keen about the emotional qualities of certain words, and the sway they can give a speaker, just by their associations. Consider the possible power of: winner, loser, infantile, powerful, lovely, courage, freedom, radical. How are these kinds of words employed to generate a certain response in the listener? What purposes are served?


How do you move a listener along to your conclusion? Certain phrases help a speaker move us from one idea to another, regardless of whether strong connection or evidence has been established. Don't let phrases like these lull your assessment of the argument: "Naturally..."; "Certainly then..."; "Surely..."; "Without question..."


Jacobs points out 3 ways posing questions helps a persuader do her work.
1. A question can substitute for a request (recall the peas and spinach).
2. While a listener is searching for an answer, the speaker can give his own answer to the question. The listener is more likely to accept it than if it were given as an assertion. 3. A question can have a suggestion embedded in it. Sales people skillfully use questions to lead the listener and control the discussion.


We've all heard "never say never"; any totalizing statement is likely to result in a fallacy. But words like "don't" and "must" creep in and can give a writer's statements and indisputable air.


The genetic fallacy

This is fallacy hinges on a confusion of causal explanation with rational justification. You may be able to explain how you came to hold a certain idea based on your past experience, such as upbringing, education, or many other factors. Thus, the causes of my belief that "2 is the square-root of 4" might include that I had to memorize this once. But this is not a justification of the belief; this would require instead that I furnish a mathematical proof (deductively valid set of inferences) to establish it. Reasoning that offers an explanation of the former sort in place of a justification of the latter sort commits the genetic fallacy. It is fallacious because the causes of someone's belief are not in general relevant to its truth or falsity. Rather, we should demand reasons. There are many forms of this fallacy. For example, some claim that because a belief in God is motivated by a need for a heavenly father to replace our mortal human parents. But even if this were true, it is logically irrelevant to the truth or falsity of the existence of God.

Argumentum ad hominem

This fallacy occurs when someone argues against a claim or position by attacking its holders in logically irrelevant ways. Even damaging and true accusations against the holder of a belief do not refute the belief! Often in environmental debate people think they can discredit a view by asserting that it is held by "wackos" or "corporate pigs" or "elitists." The point is not that name-calling is not nice; rather, who holds a belief is irrelevant to its truth. The error is not in criticizing someone on personal grounds, but in going from there to infer that some statement that this person believes is therefore false.

One exception is when the very fact that a person (perhaps a supposed authority or authority) holds a belief has been offered as a reason to accept it. In that case information calling the reliability of the person into question would, if true, be relevant to the argument.


This fallacy turns on switching the meanings of words used in the course of an argument. Consider the argument with two premises:
1. Only man is rational.
2. No woman is a man.
3. No woman is rational.
"Man" is used in 1. in the sense of the human species in comparison to others; in 2. it refers to one of the two human sexes; the argument equivocates or switches between them, causing an obviously false conclusion, even though it appears to logically follow. Carefully attend to the meanings of words in what you read!!! Once found, just substitute the ambiguous words with an unambiguous phrase and argument will be obviously invalid:
1. Only humans are rational.
2. No woman is male.
3. No woman is rational.
This fallacy becomes harder to spot the more abstract are the terms in the argument.

The black-or-white fallacy

(or the either-or fallacy, or the fallacy of thinking in extremes)

Some terms are vague in the sense that they may apply to a range of things that is not sharply defined. An area of permanent standing water is clearly a wetland; a dry mountain top clearly is not. But what about a field that is seasonally flooded? Where do you draw the line? No sharp one exists. For practical purposes we have to draw one, but any such line may be arbitrary in the sense that no conclusive reason can be given for drawing it exactly where we did.

But if one argues that since an area is not a lake it is not a wetland - since it is not in one category, it must be in the other extreme - commits this fallacy. Often justifications are offered for this move, such as "it's just a matter of degree" and "any line you draw is arbitrary." But differences of degree as well as of kind do exist in the world, and some differences of degree are just as important as differences of kind.

Jumping to a conclusion

What's wrong with concluding something about all Western students on the basis of interviewing only 10? (It has to do with sampling.) Other variations have to do with generalizing to a wider set of claims that the evidence offered supports. Pesticide residues may be a cause of cancer, but they are probably not the cause.

Straw opponent

This common strategy occurs when instead of attacking one's opponent's actual beliefs, the speaker attacks a less defensible position that superficially resembles the position held by the opponent. Consider this argument:
Some environmentalists argue that the interests of nonhuman species should be given consideration in decisions about economic development. Every time there is an advance in industry, some animals may be harmed. But if we halt all economic growth and technological development, human beings will be forced to have far greater impacts on the environment that otherwise.
Clearly "halting all development" implies something quite different than does "given consideration."

Begging the question

If an argument depends for one of its reasons or assumptions on a statement that is identical or equivalent to the conclusion drawn, it is "circular" or "question-begging."
The Forest Service is corrupt, for the clear reason that it is sold out.
Such arguments really go nowhere!! Note that a suppressed or presupposed assumption might also be the conclusion, making this fallacy less obvious!

Loaded questions

This fallacy occurs in a question that assumes the truth of one or more fallacies, but doesn't offer evidence to support them. The listener is asked or led into a situation where response implies agreement with these assumptions. "Is your company still evading enforcement actions by the EPA?"

Misrepresentation of references

Detecting this fallacy requires knowing the true context or statement on which an argument depends for support. If an author advocating ecosystem management acknowledged a need to reduce the population of some animal in order to attain a more balanced species composition, it would be wrong to pull out one statement she may have made and suggest she is in favor of unconstrained hunting. This fallacy also applies to the uses of statistics; always examine the full context; ask what has been omitted, what else might have happened that explains or refutes a connection that has been "proven" with statistics.

Argument from ignorance

There is insufficient evidence to establish that pesticide residues cause cancer; therefore they do not cause it.
Ignorance or lack of proof or evidence shows neither truth or falsity!!

Post hoc ergo propter hoc

This Latin phrase means "after this, therefore because of this," and it denote the logical fallacy in arguing that one thing caused another just because it happened before it. It is a special case of the general problem of inferring causation from correlation. One example is the observation of increased stork sightings and increased births in a town in Germany over a period of 20 some years. Was there a causal relation? No, both observations were the result of a third factor, probably increased population levels.

Face value

Rather than offering any reasons, a persuader may try to get us to accept what he says on the basis of force of personality, intimidation or bullying, or appeal to a supposed authority who actually is not an expert on the subject. None of these bases should convince us.

Burden of proof

Normally, we want to see a convincing degree of proof before we accept a new view as true. Those promoting that view have "the burden of proof." Shifting the burden of proof to another party is an important strategy. In the case of health effects of pollution, for example, the situation in the US has been that for anyone to seek redress for exposure to pollution, they must prove that it cased their health problems. An alternative, advocated by some environmentalists, is that those proposing to undertake a polluting activity should have to first prove it is safe before being allowed to proceed. A problem arises because scientific knowledge is characterized not by absolute certainty, but by degrees of probability. Therefore the Precautionary Principle is favored by environmentalists: when the risks are great enough, the burden of proof should be with those proposing polluting or damaging activities. In other words, a cautious stance toward risk, and a concern for the magnitude of future damages, justify acceptance of a new idea (restraints on business as usual) despite lack of positive scientific proof. Showing probable harm is sufficient, in environmentalists' view, to err on the side of safety.

Just when a claim that proof is available that an activity is safe is a difficult matter to judge. When shifting the burden of proof to (or from) environmentalists is likely to remain a very particular decision in every case.

Ignoring the issue

Many a political candidate can be observed responding to a question by talking about something she or he wanted to talk about instead. When irrelevant considerations are raised as a way of distracting attention from valid arguments on the other side, the result is hardly a valid response.

Intent signals

These are things to look for in persuasive language that reveal possibly self-serving motivations. For some purposes self-interest is fine. But too much of it, especially in the apparent pursuit of helping others, should cause us to question the integrity of the speaker. Whether the presence of any of these in writing is cause for rejection requires analysis; their presence should call up further examination.

Us vs. Them

Does the speaker see two "sides," with the other side being in some way inferior or denigrated? This happens all the time in environmental discourse, and often tends to cloud the real issues, and impede useful analysis. Many techniques of propaganda employ this technique: name calling, touting how great it is to "belong," using one-sided testimonials of famous people, simplifying issues for slogans, emphasizing being on the right side of the competition.


Although there is nothing wrong with asserting superiority, it can suggest a need that is stronger than the desire to give a sound argument.

Absolute certainty

Science doesn't provide it; scholarly research doesn't. Mathematics has it, but only within its self-defined deductive systems. When someone asserts they know something with absolute certainty, it can really only be based on self-evidence, faith, or mythology.

Righteous indignation

To quote Jacobs (1994, p. 74):
When someone is so full of guiltless virtue and vengeance because of "unjust treatment," his information is likely to be biased and inaccurate. Ultimately, this could hurt a worthy cause. Admittedly, what is truth and what is worthy are difficult things to know. But if this is not appreciated by a persuader, it could indicate he has taken an easy path to his position. It shows he may not have carefully analyzed his assertions. It is not likely he has open-mindedly compared his ideas to other viewpoints. The listener should thus question his information.


Most groups demand some degree of allegiance of their members. Knowing the agenda of any groups with which a speaker affiliates herself is helpful. Some agendas are self-serving; some are more genuinely sincere. It's hard to know without finding out.

These books were the source of ideas presented above:

Jacobs, D. T. (1994). The bum's rush: The selling of environmental backlash. Boise, ID: Legendary.

Thomas, S. N. (1977). Logical reasoning in natural language. Seattle: ASUW.

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