Exercise 18 Answers
Philosophy 102 (Maher) Spring 2009
1. Missing premise: Higher life forms are organized beings. No organized beings are things that evolved through merely random processes. All higher life forms are organized beings. No higher lif
Lecture 5 Argument Forms; Proving Invalidity
Patrick Maher
Philosophy 102 Spring 2009
Alternative notation
So far, when putting arguments in logical form, we have written therefore to indicate the conclusion. Example All men are mortal. Socrates is
Lecture 23 Mills Methods
Patrick Maher
Philosophy 102 Spring 2009
Introduction
Mills methods are inductive methods for nding the cause of a phenomenon. They were described by John Stuart Mill, a 19th century English philosopher. There are ve metho
Lecture 2 Recognizing Arguments
Patrick Maher
Philosophy 102 Spring 2009
Tests for whether a passage contains an argument
Fundamental test Is the author presenting some statements as reason to believe another one? Yes argument. No nonargument. A
Exercise 19
Philosophy 102 (Maher) Spring 2009
Translate the following statements into symbolic form using capital letters to represent simple statements. 1. New Zealand does not have nuclear weapons. 2. Either Brazil or Argentina destroys its rain
Exercise 17
Philosophy 102 (Maher) Spring 2009
1. Symbolize the following arguments using the given letters, then reduce the number of terms and put the arguments into standard form. Determine whether the arguments are valid and name any fallacies c
Lecture 4 Validity, Soundness, Strength, and Cogency
Patrick Maher
Philosophy 102 Spring 2009
Validity
Denition A valid argument is an argument in which the conclusion follows necessarily from the premises (i.e., it is impossible for the premises t
Lecture 3 Deduction and Induction
Patrick Maher
Philosophy 102 Spring 2009
Following with necessity
The conclusion of an argument follows necessarily from the premises if it is impossible for the premises to be true and the conclusion false. Exampl
Lecture 9 Fallacies of Presumption, Ambiguity, and Grammatical Analogy
Patrick Maher
Philosophy 102 Spring 2009
Fallacies of presumption
Denition Fallacies of presumption: The premises presume what they purport to prove. We will cover: Begging the
Yiru Chen
NetID: ychen376
Assignment #1
P18
1. Since identical twins, who have the same genes, are more likely to have the same blood
pressure than fraternal twins, who share half the same genes, we can conclude that (high blood
pressure is inherited.)
Id
Exercise 26 Answers
Philosophy 102 (Maher) Spring 2009
1. (a) p(E|H2 ) > p(E|H1 ) so, by the law of likelihood, E favors H2 over H1 . (b) p(H2 |E)/p(H1 |E) = 1 > 2/3 = p(H2 )/p(H1 ) so, by the denition of favoring, E favors H2 over H1 . (c) p(H1 |E)
Yiru Chen
NetID: ychen376
Assignment #11
P137
2. My last pair of Brand X running shoes had (unnamed) design, were comfortable, gave
excellent support, and lasted a long time.
My new pair of Brand X running shoes have the same (unnamed) design.
My new pair
Yiru Chen
NetID: ychen376
Assignment #13
P230
1. 1/2
2. 1/2
3. 1/8
4. 7/8
5. 1
6. 4/523/51
8. a. 1/2
b. 1/4
11. 1/3651/365
P249
1. a. 1/1000
b. -0.5
c. -2.5
d. -1.5
3. a. 0.6
b. 50
c. 146
d. decision under risk
e. invest in stock
7. a. turn in=10
raffle=2
Predicate: An expression with blanks, such that when names are put into the blanks, the result is a
sentence
Arity: Number of blanks
Reflexive: (For every x) xRx (=, similar to) irreflexive: (For every x) ~xRx (<, )
Symmetric: (For every x, y)(xRyyRx)(=,
Yiru Chen
NetID: ychen376
Assignment #12
P181
1. a. Male rhesus macaques are better at recognizing fertility signals in female macaques that
they know than in females from other groups, specific occurrence
b. Fertile females have darker faces. & When Rhes
Yiru Chen
NetID: ychen376
Assignment #4
P340
Part I
9.
p
T
F
T
F
T
F
T
F
Valid.
11.
p Q
T T
F T
T F
F F
T T
F T
T F
F F
Invalid.
q
T
T
F
F
T
T
F
F
r
T
T
T
T
F
F
F
F
r
T
T
T
T
F
F
F
F
~p
F
T
F
T
F
T
F
T
~r
F
F
F
F
T
T
T
T
pvq
T
T
T
F
T
T
T
F
(p v q)r
T
T
T
Yiru Chen
NetID: ychen376
Assignment #10
P114
Part I
1. Reference class: Young people eligible to vote, who ages 18-29
Attribute class: Voters in midterm elections
Strong
3. Reference class: Young voters
Attribute class: Voters voted Democratic
Weak becau
Yiru Chen
NetID: ychen376
Assignment #5
P360
Part I
1. No novelists are writers.
3. Some American automobiles are not elctric
5. Some electric cars are battery powered.
7. Some pro football players are dancers.
9. No stockbrokers are rich.
Part II
1. It a
Yiru Chen
NetID: ychen376
Assignment #6
P385
2. All who takes in the Times are well educated.
All who are well educated can read.
-All who takes in the Times can read.
All who takes in the Times can read.
No hedgehogs can read.
-No hedgehogs takes in the
Yiru Chen
NetID: ychen376
Assignment #3
P331
Part I
1. q~r
3. qr
5. ~r~q
7. q p
9. ~(~r) / r
11. q~p
13. p v (p~q) r v (p~q)
15. r~(p v q) / r~p~q
Part II
1. Logic is easy but and symbols cannot be used.
3. Logic is not fun and symbols cannot be used.
5.
Lecture 25 Bayess Theorem
Patrick Maher
Philosophy 102 Spring 2009
Bayess theorem
Suppose H is a hypothesis, E is some evidence, and we want to calculate p(H|E ). Often p(E |H) is easier to calculate than p(H|E ). Bayess theorem allows us to calcu
Lecture 24 Probability
Patrick Maher
Philosophy 102 Spring 2009
Kinds of probability
Example You know that a coin is either two-headed or two-tailed but you have no information about which it is. The coin is about to be tossed. What is the probabi