WEEK 8

Question 1

modesty in claims

Answer 1

more modest to say

• “someone stole the car”

than

• “Sam stole the car”

Question 2

What opportunities do modest claims have?

Answer 2

more opportunities to be true

• “Sam stole the car” - need evidence that Sam did it
• “Someone stole the car” - need evidence that Sam did it or Tom did it or Jerry did it, etc.

Question 3

modest defensibility rule

Answer 3

if a claim is at all defensible, a more modest version will either maintain or increase its defensibility

Question 4

exception to defensibility rule

Answer 4

neither are practically possible

• “He will win 2 trillion to nil”
• “He will win by a 2 trillion margin”

Question 5

logical strength

Answer 5

• claim X is logically stronger than claim Y if and only if you can derive Y from X but not X from Y
• X, therefore Y holds true but Y, therefore X doesn’t hold true

Question 6

how can you diminish logical strength?

Answer 6

• Existential introduction rule
  
  • “John is ill, therefore someone is ill”
• Disjunction introduction rule
  
  • “This coffee has sugar, therefore is coffee has sugar or milk”
• Conjunction elimination rule
  
  • “The winter will be cold and dry, therefore the winter will be cold”

Question 7

What does diminishing logical strength do for modesty?

Answer 7

• claims are more modest and therefore more defensibly
• because logically stronger claims commit themselves more than logically weaker ones
• logically stronger cliams have fewer opportunities to be true

Question 8

Duhem-Quine thesis

Answer 8

hypotheses cannot be tested in isolation as they don’t have consequences on their own

Question 9

Quien’s web of belief metaphor

Answer 9

all of our beliefs are nestled in an interconnected web of support

Question 10

what are systems made up of?

Answer 10

central hypotheses and auxiliaries

Question 11

1. word for when system is true
2. word for when system is false

Answer 11

1. confirmed
2. disconfirmed

Question 12

If a consequence is false, will adding premises rectify it?

Answer 12

• no because classical logic is monotonic
• something must be removed or replaced

Question 13

analogical reasoning

Answer 13

• use of such reasoning is widespread throughout the scientific and everyday domains
• e.g. Newton’s law of gravity

Question 14

what decides the stength of an analogy?

Answer 14

how much we have had to abstract away in order to find commonalities

Question 15

completely uninformative analogy

Answer 15

• abstract away so much that what is left behind is trivial
• e.g. Newton’s equations have lots of variables so others will too

Question 16

informative analogy

Answer 16

only one layer is abstracted away

e.g. isomorphism = bijective mapping between objects that preserves relations