PHI2100-01 Midterm Review Part One: Arguments & Fallacies1. Argument - set of premises that give us reason to believe that a conclusion is true.V.Explanations - arguments attempt to show that something is true v. Explanations attempt to show how something is trueThreats & bribes - arguments aim to give you reason to believe something is true v. Threats and bribes give you a reason in the sense of a motive to believe something.2. How to identify arguments -look for conclusion and PREMISES3. Requirements for a good argument (in general): 1) A good argument must have all true (or at least plausible) premises 2) Premises must support conclusion - that gives us some reason to believe that the conclusion is true4. Argument in standard form :- A list of premises separated from the conclusion by a horizontal lineEx. 1. All men are mortal 2. Socrates is a man 3. Therefore, Socrates is mortal5. Deductive Argument- the support of the premises is measured through validity and soundness- Forms of valid arguments • Modus Ponens: 1) If P, then Q2) P___________ 3) Therefore, Q• Modus Tollens: 1) If P, then Q 2) Not Q________ 3) Therefore, not P • Hypothetical Syllogism: 1) If P, then Q 2) If Q, then R_________ 3) Therefore, if P, then R • Disjunctive Syllogism: 1) P or Q 2) Not Q_____ 3) Therefore, P Or 1) P or Q 2) Not P_______ 3) Therefore, Q6. Validity and soundness1) A valid deductive argument - if the premises are true, then the conclusion has to be true (truth-preserving)2) An invalid deductive argument - is an argument that can have premises that are true but the conclusion can be false3) Deductively sound means if a deductive argument is valid AND the premises are true.4) Unsound deductive argument is an argument that is either invalid or the premises are not true or both.7. Antecedent and consequent of conditional (if then) statements- If x (antecedent), then y (consequent)8. Inclusive v. Exclusive - Disjunctive statements- Inclusive - the sense of "or" here does not rule out both parts (disjunct) of the argument; the statement can be true if they are both true (in logic this is used!) ex. If you want to go snorkeling, go to the Florida Keys or Hawaii- Exclusive - the sense of "or" here does rule out both parts (disjuncts) of the argument. ex. Either you drive or I drive- Disjunctions are a compound composition using the connective "or"9. Inductive arguments - Arguments where the conclusion follows from the premises not with necessity but with probability -> assessed through strength and cogency- Ex. 1) Josh is left handed2) 90% of left handed people experience difficulty using can openers made for right handed people3) Therefore, Josh has trouble using can openers for right handed people10. Inductive strength and cogency- Inductive strength is measured to the extent that the conclusion is probable given the premises -> An inductive argument has strength, in so far as the premises (if true) make the conclusion more probable. This is a matter of degree (unlike validity).- Inductive cogency is strong strength and premises being true11. Abductive Argument- Arguments to the best explanation- The conclusion stands as an explanation for the facts given in the premises- The conclusion stands as an explanation for the facts given in the premisesEx. 1) I have a headache 2) I'm having trouble concentrating 3) So, I must have a brain tumor12. 4 features of a good Abductive argument1) Simplicity - go with least complicated explanation2) Coherence - go with explanation that's consistent with what experts about the subject (or other related subjects) already believe to be true3) Testability/predictive power - go with the theory that yields the most predictions that can be confirmed or disconfirmed4) Comprehensiveness - go with the explanation that leaves the least things unexplained13. Formal & informal fallacies- Fallacy is an instance of poor reasoning, faulty inference- Formal fallacy - faulty reasoning where the fault is in the structure or form if the argument (all invalid arguments are formal fallacies)A) Affirming the consequent: 1) If p, then q 2) q_________ 3) Therefore pB) Denying the antecedent: 1) If p, then q 2) Not p_________ 3) Therefore, not qC) Affirming the disjunct: 1) Either P or Q 2) P_____________ 3) Therefore, not QD) Undistributed middle: 1) All A is P 2) All B is P_________ 3) Therefore all B is A- Informal fallacies- when the fault of the reasoning lies in the content of the argument, rather than the formA) Equivocation: when the same word is used with 2 different meaningsB) False dilemma: when a limited number of options are given (usually 2) when there are actually more optionsC) Begging the question: to assume, in your premises, what you are trying to proveD) Straw man fallacy - when interpreting another's theory or argument, not practicing the principles of charity and fidelity (see point #14 & #15 of study guide for Part One)E) Ad Hominem - 3 types 1) abusive - attacks the person making an assertion or argument rather than the argument or assertion itself. 2) circumstantial - occurs when one points our the relationship of the person making anassertion and the circumstances of that person 3) Tu quoque - an attack that notes that one does not practice what he preachesF) Illicit appeal to authority - appealing to authority inappropriately when: - The person is not qualified to have an expert opinion on the subject - Experts in the field disagree on the issue - The authority was not being serious or was making a jokeG) Hasty generalization - sample size is too small to support the conclusion14. Principle of charity:- Maximize the sound of argument you are discussing by giving someone the best possible strongest argument, must assume premises are true and valid. "Attacking the strong man"15. Principle of fidelity:- When attacking or discussing the argument, you want to attack the argument as accurate as possible; you want to have the most accurate argument. Actually capturing what the person is saying and understanding it.Part Two: Misleading Numbers/Graphs1. All claims of the form "the average of X is Y" is ambiguous because "average" can mean "median," "mode," or "mean"2. Mean, median, mode- Mean: Arithmetic averages of a range of values (add values, divide by # of values)- Median: midpoint value in a range of values ordered from least to greatest- Mode: value that occurs most frequently in a range of values3.