1. Logic

2. Definition of Logical Writing
Logic is a formal system of analysis that helps writers invent, demonstrate, and prove arguments.
It works by testing propositions against one another to determine the accuracy.
People often think they are using logic when they avoid emotion or try to argue based on common sense, such as “Everyone should look out for their own self-interests” or “People have the right to be free.”
Unemotional or common sense statements are not always equivalent to logical statements.
To be logical, a proposition must be tested within a logical sequence.

3. The most famous logical sequence: Syllogism – developed by Aristotle
Premise 1: All men are mortal.
Premise 2: Socrates is a man.
Conclusion: Therefore, Socrates is mortal
Premise 2 is tested against Premise 1 to reach the logical conclusion.
With this system, if both premises are considered
Valid, there is no other logical conclusion than deter-
mining Socrates is mortal.

4. Logic Vocabulary Premise: proposition used as evidence in an argument.
Conclusion: Logical result of the relationship between the premises – Often serve as thesis for the argument
Argument: the assertion of a conclusion based on logical premises.
Syllogism: the simplest sequence of logical premises and conclusions
Enthymeme: A shortened syllogism which omits the 1st premise, allowing the audience to fill it in.
Induction: a process through which the premises provide some basis for the conclusion
Deduction: a process through which the premises provide conclusive proof for the conclusion

5. Logical Fallacies Common errors in reasoning that will undermine the logic of your argument
Slippery Slope – based on the premise that if A happens then so will B, C, … X, Y, & Z will happen too, basically, equating that A = Z. So, if we don’t want Z to occur, A must not be allowed to occur either.
Example: If we ban Hummers because they are bad for the environment, eventually the government will ban all cars, so we should not ban Hummers.
In this example , the author is equating banning Hummers with banning all cars, which is not the same thing.
Hasty Generalization - Conclusion based on insufficient or biased evidence. In other words, you are rushing to a conclusion before you have all the relevant facts.
Example: Even though it’s only the first day, I can tell this is going to be a boring course.
In this example, the author is basing his evaluation of the entire course on only the first day, which is notoriously boring and full of housekeeping tasks for most courses. How can the author make a reasonable evaluation of the course?

6. Post hoc ergo propter hoc – Assumes that if “A” occurred after “B” then “B” must have caused “A”.
Example: I drank bottled water and now I am sick, so the water must have made me sick.
The assumption is that if one event chronologically follows another the first event must have caused the second. But the illness could have been caused by other underlying factors – food poisoning, a stomach bug, etc. There is no reason, without more evidence, to assume the water caused the person to be ill.
Begging the Claim: The conclusion that the writer should prove is validated within the claim.
Example: Filthy and polluting coal should be banned.
This argues that coal pollutes the earth and thus should be banned would be logical. But the very conclusion that should be proved, that coal causes enough pollution to warrant banning its use, is already assumed in the claim by referring to it as “filthy and polluting.”

7. Circular Argument– Restates the argument rather than actually proving it.
Example: Mrs. Magnusson is a good communicator because she speaks effectively.
The conclusion that Mags is a “good communicator” and the evidence used to prove it “she speaks effectively” are basically the same idea. Specific evidence such as using everyday language, breaking down complex problems, or illustrating her points with humorous stories would be needed to prove either have of the sentence.
Either/Or: This conclusion that oversimplifies the argument by reducing it to only 2 options.
Example: We can either stop using cars or destroy the earth.
This example shows only 2 choices being presented, yet there is a range of options available – i.e.: developing cleaner technology, car-sharing systems for necessities and emergencies or better community planning to discourage daily driving.

8. Ad hominem– This is an attack on the character of a person rather than his or her opinions or arguments.
Example: Green Peace’s strategies aren’t effective because they are all dirty, lazy hippies.
In this example, the author doesn’t even name particular strategies Green Peace has suggested, much less evaluate those strategies on their merits. Instead, the author attacks the characters of the individuals in the group.
Ad populum– Emotional appeal that speaks to the positive (such as patriotism, religion, democracy, etc.) or negative (such as terrorism or fascism) concepts rather than the real issue at hand.
Example: If you were a true American you would support the rights of the people to choose whatever vehicle they wanted to buy.
In this example, the author equates being a “true American”, a concept that people want to be associated with, particularly in a time of war, with allowing people to buy any vehicle they want even though there is no inherent connection between the 2.

9. Red Herring– A diversionary tactic that avoids key issues, often by avoiding opposing arguments rather than addressing them.
Example: The level of mercury in seafood may be unsafe, but what will fishers do to support their families.
This example shows the author switching the discussion away from the safety of the food and talks about instead the economic issue, the livelihood of those catching fish. While one issue may affect the other it does not mean we should ignore possible safety issues because of possible economic consequences to save a few individuals.
Straw Man– This move oversimplifies an opponent’s viewpoint and attacks that hollow argument.
Example: People who don’t support the proposed state minimum wage increase hate the poor.
This example shows the author attributing the worst possible motive to an opponent’s position. In reality, however, the opposition probably has more complex and sympathetic arguments to support their point. By not addressing those arguments, the author is not treating the opposition with respect or refuting their position.

10. Argumentum Populum – Bandwagon – Appeal to People
An appeal to the people argues that since most people do something, you should too!
Example: Everyone is jumping off a cliff – are you going to jump too?
Fallacy of Division:
This argues that if a whole unit has a quality, then each part must have that quality.
Example: The universe has existed for 15 billion years. The universe is made up of molecules. Therefore, each of these molecules in the universe has existed for 15 billion years.

11. Fallacy of Composition:
This assumes that because every part has a characteristic, the whole unit will also have that characteristic.
Example: A car makes less pollution than a bus. Therefore, cars are less of a pollution problem than busses.
Fallacy of False Dilemma:
A fallacy of false dilemma offers fewer options than really exist.
Example:
Salesman: Face it Doris, all you’ll ever be is a secretary in this company.
Doris: No – someday I’ll be your boss and you can kiss your job good-bye.

12. Example: Go to sleep right now or the monster will come and get you.
Appeal to Force: An appeal that convinces the public by arousing fears.
Example: Go to sleep right now or the monster will come and get you.
- Vote for me or bad things will happen.
Argument from Ignorance:
An argument from ignorance uses information that has not been proven to be true or false.
Example: Although pictures and videos exist, it’s never been proven that Big Foot or the Loch Ness Monster really exist.

13. Moral Equivalence– This fallacy compares minor misdeeds with major atrocities.
Example: That parking attendant who gave me a ticket is as bad as Hitler.
This example shows the author comparing the relatively harmless actions of a person doing their job with the horrific actions of Hitler. This comparison is unfair and inaccurate.
Citation:

14. Moral Equivalence– This fallacy compares minor misdeeds with major atrocities.
Example: That parking attendant who gave me a ticket is as bad as Hitler.
This example shows the author comparing the relatively harmless actions of a person doing their job with the horrific actions of Hitler. This comparison is unfair and inaccurate.
Citation:
Begging the Question: When a premise in an argument assumes the conclusion to be correct.
Example: I said, “I am always right.” Because I said it, it must be right. Conclusion: I am always right.

15. Definition of Rhetoric
Quick Definition: The art that humans use to process all the messages we send and receive.
We see these messages every day in forms of books, magazines, conversations, the news, in music and art, and in the movies and TV shows we watch.
We use rhetoric every day, whether we use it deliberately or not, and we all respond to rhetoric, whether we are conscious of it or not. Since the world around us carries messages that get received or lost or transformed, to understand rhetoric is to understand the world better and to participate in it more fully.

16. Remember the following:
Consider the following elements when writing:
The subject and the kinds of evidence used to develop it
The audience and their knowledge, ideas, attitudes, and beliefs
The character of the writer – particularly how the writer might use his/her personal character effectively in the text.
The writer/speaker needs to understand how it appeals to the audience:

17. Logic
Logic reasoning offers a clear, reasoned central idea (or ideas) and developing it (or them) with appropriate evidence to appeal to an audience’s sense of logic.

18. Ethics
The writer offers evidence that he or she is credible – knows important and relevant information about the topic at hand and is a good, believable person who has the audience’s best interest in mind.

19. Emotion
By drawing on the emotions and interests of the audience so they will be sympathetically inclined to accept and buy into the central ideas and arguments