phil 2303 intro to logic logicalfallacies fallacy incorrect

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phil 2303 intro to logic

phil 2303 intro to logic

logicalfallacies

logicalfallacies

fallacy incorrect reasoning in argumentation resulting in a misconception

fallacy incorrect reasoning in argumentation resulting in a misconception

informalfallacies stem from inductive arguments, not deductive ones.

informalfallacies stem from inductive arguments, not deductive ones.

deductive argument the premises provide a guarantee of the truth of the conclusion. In

deductive argument the premises provide a guarantee of the truth of the conclusion. In a deductive argument, the premises are intended to provide support for the conclusion that is so strong that, if the premises are true, it would be impossible for the conclusion to be false.

The classic example of a deductive argument: (1) All men are mortal. (true) (2)

The classic example of a deductive argument: (1) All men are mortal. (true) (2) Socrates is a man. (true) Therefore: (3) Socrates is mortal. (true)

inductive argument the premises provide reasons supporting the probable truth of the conclusion. In

inductive argument the premises provide reasons supporting the probable truth of the conclusion. In an inductive argument, the premises are intended only to be so strong that, if they are true, then it is unlikely that the conclusion is false.

An example of a strong inductive argument would be: (1) Every day to date

An example of a strong inductive argument would be: (1) Every day to date the law of gravity has held. Therefore: (2) The law of gravity will hold tomorrow.

the majority of our time will consist of evaluating inductive arguments, and informal fallacies.

the majority of our time will consist of evaluating inductive arguments, and informal fallacies.

ad baculum

ad baculum

ad baculum (fear of force): the fallacy committed when one appeals to force or

ad baculum (fear of force): the fallacy committed when one appeals to force or the threat of force to bring about the acceptance of a conclusion.

The ad baculum derives its strength from an appeal to human timidity or fear

The ad baculum derives its strength from an appeal to human timidity or fear and is a fallacy when the human timidity or fear appeal is not logically related to the claim being made. In other words, the emotion resulting from a threat rather than a pertinent reason is used to cause agreement with the purported conclusion of the argument. The ad baculum contains implicitly or explicitly a threat. Behind this threat is often the idea that in the end, "Might makes right. " Threats, per se, however, "Might makes right. " are not fallacies because they involve behavior, not arguments.

‘ad baculum’ baculum logical structure person L says accept argument A or event x

‘ad baculum’ baculum logical structure person L says accept argument A or event x will happen. event x is bad, dangerous, or threatening. therefore, argument A is a good argument.

‘ad baculum’ baculum example: Chairman of the Board: "All those opposed to my arguments

‘ad baculum’ baculum example: Chairman of the Board: "All those opposed to my arguments for the opening of a new department, signify by saying, 'I resign. '"

‘ad baculum’ baculum example: I'm sure you can support the proposal to diversify into

‘ad baculum’ baculum example: I'm sure you can support the proposal to diversify into the fast food industry because if I receive any opposition on this initiative, I will personally see that you are transferred to the janitorial division of this corporation.

are there times when ‘ad baculum’ arguments are not fallacious?

are there times when ‘ad baculum’ arguments are not fallacious?

the appeal is not irrelevant when the threat or the force is directly relevant

the appeal is not irrelevant when the threat or the force is directly relevant to the conclusion or is, itself, the subject of the argument. example: study your notes, [or] you will fail the test.

ad hominem

ad hominem

ad hominem (abusive and circumstantial): circumstantial the fallacy of attacking the character or circumstances

ad hominem (abusive and circumstantial): circumstantial the fallacy of attacking the character or circumstances of an individual who is advancing a statement or an argument instead of trying to disprove the truth of the statement or the soundness of the argument. Often the argument is characterized as a personal attack.

The personal attack is also often termed an "ad personem argument": the statement or

The personal attack is also often termed an "ad personem argument": the statement or argument at issue is dropped from consideration or is ignored, and the locutor's character or circumstances are used to influence opinion. "tu quoque" or charging the locutor with "being just like the person" -rather than trying to disprove a remark about someone's character or circumstances, one accuses the locutor of having the same character or circumstances. In other words: “I know my argument is badbut not as bad as his. ”

‘ad hominem’ hominem logical structure Person L states argument A. Person L’s character or

‘ad hominem’ hominem logical structure Person L states argument A. Person L’s character or circumstance is not satisfactory. therefore, argument A is not a good argument.

‘ad hominem’ hominem example: Francis Bacon's philosophy should be dismissed since Bacon was removed

‘ad hominem’ hominem example: Francis Bacon's philosophy should be dismissed since Bacon was removed from his chancellorship for dishonesty.

‘ad hominem’ hominem example: Prof. Smith says to Prof. White, "You are much too

‘ad hominem’ hominem example: Prof. Smith says to Prof. White, "You are much too hard on your students. " Prof. White replies, "But certainly you are not the one to say so. Just last week I heard several of your students complaining. "

are there situations when ‘ad hominem’ arguments hominem should be considered?

are there situations when ‘ad hominem’ arguments hominem should be considered?

Det. Mark Fuhrman The prosecution’s case against O. J. Simpson, even with DNA evidence

Det. Mark Fuhrman The prosecution’s case against O. J. Simpson, even with DNA evidence at the crime scene, was cast into reasonable doubt because of Det. Fuhrman’s character and past pejorative statements about African Americans.

ex-post facto statistics

ex-post facto statistics

ex-post facto statistics (past event probability): This fallacy occurs when we attempt to supply

ex-post facto statistics (past event probability): This fallacy occurs when we attempt to supply mathematical analysis to events that have occurred in the past.

ex-post facto statistics This argument is a great for the assumptions that something ‘supernatural’

ex-post facto statistics This argument is a great for the assumptions that something ‘supernatural’ or ‘transcendent’ has taken place in our lives. It also allows for us to think that we are somehow special, or children of destiny because of certain events.

ex-post facto statistics (example). Today I ran into Johnny Depp on Rodeo Drive while

ex-post facto statistics (example). Today I ran into Johnny Depp on Rodeo Drive while vacationing in LA. Out of all the thousands of movie stars I could have run into there- I ran into him, my favorite actor!

ex-post facto statistics (example). The odds of life evolving from a single cell organism

ex-post facto statistics (example). The odds of life evolving from a single cell organism to the complexity of what we see now is 100 to the 23 rd power (or 100 with 23 zeros behind it) 10000000000000

complex question

complex question

complex question the fallacy of phrasing a question that, by the way it is

complex question the fallacy of phrasing a question that, by the way it is worded, assumes something not contextually granted, assumes something not true, or assumes a false dichotomy. To be a fallacy, and not just a rhetorical technique, the conclusion (usually the answer to the question) must be present either implicitly or explicitly.

complex question (examples): Have you stopped beating your wife? What religion are you and

complex question (examples): Have you stopped beating your wife? What religion are you and your family? Did you commit the murder before or after you bought that drink? .

reading assignments ‘ad nauseam’ ‘ad misericordiam’ ‘ad novitum’ ‘ad populum’

reading assignments ‘ad nauseam’ ‘ad misericordiam’ ‘ad novitum’ ‘ad populum’

ad misericordiam

ad misericordiam

ad misericordiam (argument from pity or misery): the fallacy committed when pity or a

ad misericordiam (argument from pity or misery): the fallacy committed when pity or a related emotion such as sympathy or compassion is appealed to for the sake of getting a conclusion accepted.

a statement or an argument is sought on the basis of an irrelevant appeal

a statement or an argument is sought on the basis of an irrelevant appeal to pity. In other words, pity, or the related emotion is not the subject or the conclusion of the argument.

‘ad misericordiam’ misericordiam logical structure Person L argues statement p or argument A. L

‘ad misericordiam’ misericordiam logical structure Person L argues statement p or argument A. L deserves pity because of circumstance y. Circumstance y is irrelevant to p or A. Statement p is true or argument A is good.

‘ad misericordiam’ misericordiam example: Oh, Officer, There's no reason to give me a traffic

‘ad misericordiam’ misericordiam example: Oh, Officer, There's no reason to give me a traffic ticket for going too fast because I was just on my way to the hospital to see my wife who is in serious condition to tell her I just lost my job and the car will be repossessed.

‘ad misericordiam’ misericordiam example: Public Schools, K through 12, need to have much easier

‘ad misericordiam’ misericordiam example: Public Schools, K through 12, need to have much easier exams for students because teachers don't fully realize the extent of the emotional repercussions of the sorrow and depression of the many students who could score much better on easier exams.

when are ‘ad misericordiam’ arguments not fallacious?

when are ‘ad misericordiam’ arguments not fallacious?

global relief arguments are indeed relevant to the problems raised by a disaster caused

global relief arguments are indeed relevant to the problems raised by a disaster caused by a tidal wave in Sri Lanka, or a cholera outbreak in India.

ad nauseam

ad nauseam

ad nauseam (repetition or tautology): tautology the fallacy of using constant repetition, often in

ad nauseam (repetition or tautology): tautology the fallacy of using constant repetition, often in the face of massive evidence against a contention, to make it more likely to be accepted.

The ad nauseam fallacy is really more of a persuasive tactic rather than a

The ad nauseam fallacy is really more of a persuasive tactic rather than a form of logic. It attempts to persuade an audience (normally in debate-type forums) two ways: 1. By wearing down the opposition by repeating arguments that have previously been dealt with in hopes that the opponent simply gives up. 2. By deceiving the audience into thinking that the counter objections have been dealt with (when they really have not).

‘ad nauseam’ nauseam logical structure There is no ‘pure’ logical form of the ad

‘ad nauseam’ nauseam logical structure There is no ‘pure’ logical form of the ad nauseam fallacy, in that, it can take multiple fallacious forms to meet the requirement of repetition.

‘ad nauseam’ nauseam examples: various factors | psychology ‘Please sir, I didn’t do it.

‘ad nauseam’ nauseam examples: various factors | psychology ‘Please sir, I didn’t do it. ’ ‘But this is your knife, Mr. Smith. ’ ‘Please sir, I didn’t do it. ’ ‘A witness saw you stab Mr. Jones. ’ ‘Please sir, I didn’t do it. ’

‘ad nauseam’ nauseam examples: various factors | marketing ‘Get whiter ‘whites’, and redder ‘reds’

‘ad nauseam’ nauseam examples: various factors | marketing ‘Get whiter ‘whites’, and redder ‘reds’ from new Clorox laundry detergent. ’

are there situations when ‘ad nauseam’ arguments nauseam should be considered?

are there situations when ‘ad nauseam’ arguments nauseam should be considered?

ad populum

ad populum

ad populum (popular appeal or majority appeal): the fallacy of attempting to win popular

ad populum (popular appeal or majority appeal): the fallacy of attempting to win popular assent to a conclusion by arousing the feeling and enthusiasms of the multitude.

There are many variations that this fallacy can take, but the primary focus results

There are many variations that this fallacy can take, but the primary focus results in two common forms:

‘Snob Appeal’ the fallacy of attempting to prove a conclusion by appealing to what

‘Snob Appeal’ the fallacy of attempting to prove a conclusion by appealing to what an elite or a select few (but not necessarily an authority) in a society thinks or believes. (least common form, very close to ad verecundiam)

‘ad populum’ populum (snob) logical structure Person L says statement p or argument A.

‘ad populum’ populum (snob) logical structure Person L says statement p or argument A. Person L is in the elite. Statement p is true or argument A is good. .

"Bandwagon“ the fallacy of attempting to prove a conclusion on the grounds that all

"Bandwagon“ the fallacy of attempting to prove a conclusion on the grounds that all or most people think or believe it is true.

‘ad populum’ populum (band) logical structure Most, many, or all persons believe statement p

‘ad populum’ populum (band) logical structure Most, many, or all persons believe statement p is true. Statement p is true. .

‘ad populum’ populum example: Gatorade. It is the official sports drink of the NFL.

‘ad populum’ populum example: Gatorade. It is the official sports drink of the NFL.

‘ad populum’ populum example: It is well recognized by most persons that the present

‘ad populum’ populum example: It is well recognized by most persons that the present technological revolution has affected the ethical basis of the nation's institution of education. Since this belief is so widely held, there can be little doubt of its accuracy.

are there times when ‘ad populum’ arguments are not fallacious?

are there times when ‘ad populum’ arguments are not fallacious?

to remark that most physicians believe that a high fat diet is unhealthy, so

to remark that most physicians believe that a high fat diet is unhealthy, so that it follows that persons who have a high fat diet should change their eating habits, is to make a legitimate appeal.