The following lists and comment are built with the idea of a persuasive framework in mind: Position/Arguments in support of the position/evidence and appeals that support the arguments
What follows is a reference for Standards of Evaluation:
Newspapers (news articles and opinions/editorials. Online and print)
As a writer you must distinguish a news article, which is informational, from a published opinion or editorial as these are examples of persuasive writing. Informational writing and persuasive writing are subject to different Standards of Evaluation. In persuasive writing, we can use informational sources to provide context and background and to provide examples of “something.”
Weblogs (new media, frequently updated)
In information literacy, weblogs are interesting and problematic. They are online websites, produced and managed by an individual or an institution or even by a group of people with common interests, whose most recent content appears first in a list of posts. One standard for evaluating the content of a weblog is the identity/ credentials of the author.
Academic and Professional Peer Reviewed Periodicals (For example, Constitutional Commentary is published through the University of Minnesota)
Trade/Special Interest Periodicals (Popular Mechanics)
Politics and Culture Periodicals (The Nation, The Weekly Standard)
Popular or Current Affairs (Vanity Fair, People)
Let’s break support into three broad areas: evidence and appeals.
Let’s break Evidence down into understandable parts. There are a few types of evidence we can identify, describe, and evaluate:
Data or Quantitative Information (statistics, graphs, other visual data)
How to Evaluate: is it current and relevant; is it sufficient; is it representative; is the source of the data credible; does it show the magnitude or insignificance of a problem; is there a significant relationship? Does the data have context?
Potential fallacies: hasty generalization; false dilemma; slippery slope; post hoc ergo propter hoc; red herring.
Example and Illustration
How to Evaluate: is the example relevant; is it representative (one or two examples may be like many others) and appropriate; is it sufficient.
Potential fallacies: hasty generalization; false dilemma; slippery slope; apples and oranges, post hoc ergo propter hoc.
How to Evaluate: does the observer have a vested interest; is the observer reliable; is the anecdotal information relevant to the case or problem.
Potential Fallacies: ad hominem, straw man; hasty generalization; ad populum; moral equivalence; circular argument; begging the question; genetic fallacy.
Expert or Authority opinion
Experts are often used to support an argument or point. This is also called argument by authority. How to evaluate: are the experts relevant to the field or knowledgeable on the subject; is the content used relevant and appropriate? Is it sufficient? Do the experts use data and examples of their own that makes sense to the issue at hand?
Potential Fallacies: ad hominem; straw man; hasty generalization; ad populum; moral equivalence; circular argument; begging the question; genetic fallacy.
How to evaluate: is it accurate; does it reflect common usage; is it arcane; is it a stipulation? It is significant that people agree on definitions in disputes. Often differing meanings are used to confuse, misdirect an audience or frame an issue to one’s advantage, such as in the use of euphemism, ambiguity, or the use of over-narrow or over-broad definitions.
Potential Fallacies and problems: circular definition (circularity); generalization; obscurity; false dilemma; obfuscation.
We often understand reasoning by how people use evidence or how they come to conclusions, tracking their methods for doing so and why. It’s not easy to boil this down.
Deductive reasoning is a method of thinking that comes to conclusions based on premises or starting from what we might call a general observation or argument or truth and then coming to a specific conclusion based on that generalization. Think of this as a way of coming to a conclusion using rules. We can agree on a conclusion based on deduction by how well we understand and support the premises or even order them. And so we claim that a deductive conclusion has validity or formality but not necessarily truth or evidentiary value. Here’s a famous example of deductive reasoning using what’s called a syllogism.
Major premise: All men are mortal (where we agree that the attribute “mortal” is true for a class of things “men”)
Minor premise: Socrates is a man (where we agree that Socrates is not a squirrel but a “man”)
Therefore, Socrates is mortal.
Makes sense. It is important to understand from this example that someone has made the case prior to the major premise that men are mortal in the first place. We could do this with all kinds of examples. For example, there are many animals on the planet whose teeth grow rapidly. Squirrels fall into this category. We know that squirrels prepare for the winter by storing nuts. But does this mean that all animals whose teeth grow rapidly horde nuts in the winter time?
There are also many decisions people make that some people consider dangerous. We know that dangerous activity can lead to bad outcomes. Rocks climbers for example are involved in fairly dangerous activity. Banning dangerous activity will eliminate the bad outcome and save lives. Does this mean that the local government should ban rock climbing activity because it would save lives? Deductive logic does not always treat complexity all that well but at least it can help us identify problems.
One way of thinking about inductive reasoning is to think about coming to conclusions based on what we know or have observed. The origin of the word has to do with “lead to”: that something leads to something else, sort of like following a fox to its destination. Think about the word “induce,” which would seem to mean “starting something” or “beginning a process.” We want to know where the animal is going so we follow it and where it goes it goes and that’s that.
Induction also implies uncertainty, because we don’t know where the fox is going. We don’t really know if something is true until we ask certain types of questions or derive evidence that gets us closer to the truth. For example, will laws that ban one action really solve the problem? Is the opinion of a group of people really what others say it is? Inductive reasoning follows specifics to a general conclusion but we typically can’t claim that the conclusion is entirely satisfactory. We can claim, however, that it is true as a reasonable approximation. The sun will rise tomorrow is at base inductive because our experience tells us that the sun rises.
Other forms of reasoning: presenting inconsistencies; comparing to show similarity or dissimilarity; comparing to show conformity to a concept, rule, or truth.
The list above is not meant as a check list or as an issue of quantity, such as saying that every type of persuasive writing must have all of these to be successful or effective. For example, in Aristotle’s Politics, he uses authorities and example as forms of “support.” But he also apples numerous types of reasoning to his arguments. He didn’t use data. Rather he often argued by analogy, relating one thing to another thing. For example, he writes: “Again, a possession is spoken of as a part is spoken of; for the part is not only a part of something else, but wholly belongs to it; and this is also true of a possession.” He relates, moreover, the leader of a household to the leader of a state and then breaks down the similarities and differences.
Appeals to Need (everyone needs shelter, therefore homelessness is bad: see Maslow’s Hierarchy)
How to evaluate: is the appeal explicit; is it logical and appropriate to the case; is it fair?
Appeals to Values (people value community and friendships, therefore things that threaten these are bad)
How to evaluate: is the appeal explicitly stated; is it relevant to the case or subject;
Standards for arguments and conclusions:
Issues of consequence. Are there consequences to actions that authors may not have considered? In terms of analysis, you can evaluate a conclusion on these terms.
Issues of bias. Has the author considered alternative points of view in their analysis? If not, which alternatives might you or your sources provide.