King’s College London UNIVERSITY OF LONDON This paper is part of an examination of the College counting towards the award of a degree. Examinations are governed by the College Regulations under the authority of the Academic Board. BA EXAMINATION 4AANB008 Methodology SUMMER 2013 TIME ALLOWED: 2 HOURS You should attempt to answer all questions. Each question carries the same number of marks. Avoid overlap in your answers. DO NOT REMOVE THIS PAPER FROM THE EXAMINATION ROOM TURN OVER WHEN INSTRUCTED 2013 © King’s College London 1 4AANB008 1. Consider the set {London, Paris, Madrid, {Bonn, Rome}, {Paris, Madrid}} For each of the following seven items, say whether or not it is (a) a member of this set (b) a subset of this set. Paris {Paris} Bonn {Bonn, Rome} {Paris, Madrid} {} {London, Paris, Madrid, {Bonn, Rome }} Is there a general rule telling you how many subsets a given set has? 2. What is the ‘axiom of comprehension’ of naïve set theory’? Which condition did Bertrand Russell use to show that naïve set theory is inconsistent? Explain carefully how he showed this. 3. What can you infer about a set if all its members can be paired up one-to-one with the members of one of its proper subsets? Can the rational numbers be paired up one-to-one with the natural numbers? Explain the basis for your answer. Can the real numbers be paired up one-to-one with the natural numbers? Explain the basis for your answer. 4. Explain what is meant by a ‘synthetic a priori’ statement. Is there any reason to suppose that the statement the angles in any triangle add up to 180º is synthetic? Is there any reason to suppose that this statement is a priori? Can it simultaneously be understood to be both synthetic and a priori? SEE NEXT PAGE 2 4AANB008 5. Which of these are ‘de re’ claims, and which ‘de dicto’? Also say of each claim whether it is true or false. (Assume that species membership is essential to animals.) (a) (The inventor of the zip) (might not have invented the zip) (b) (It might have been the case that) (the inventor of the zip did not invent the zip) (c) (It might have been the case that) (Julius did not invent the zip) – [where it is stipulated that ‘Julius’ refers to whomever invented the zip]. (d) (Necessarily) (the first mammal on the moon was human) (e) (Necessarily) (Neil Armstrong was human) 6. What are degrees of belief? Is there any reason why rational degrees of belief should satisfy the axioms of probability? What principle, if any, governs the relation of rational degrees of belief to objective probabilities? What principle, if any, governs the way you should rationally change your degrees of belief in response to evidence? SEE NEXT PAGE 3 4AANB008 7. Suppose that the probability of having heart disease (H), being male (M), and being a smoker (S) are given by Prob (H) = 10% Prob (M) = 60% Prob (S) = 40% And suppose that Prob (H and M) = 6% Prob (H and S) = 8% Prob (M and S) = 30% For each pair of properties (H and M), (H and S), (M and S), say whether the two properties are positively dependent, negatively dependent or independent. For each of the pairs, work out the conditional probability of the first given the second. 8. Suppose that you find that the probability of a stroke among joggers is higher than in the population in general: Prob(Stroke/Jogging) = 0.25 while Prob(Stroke) = 0.2. In the absence of any further evidence, what does this indicate about the causal connection between jogging and strokes? But suppose that you then also find that: Prob(Stroke/Jogging & Male) = 0.2 while Prob(Stroke/Male) = 0.3, and that Prob(Stroke/Jogging & Female) = 0.05 while Prob(Stroke/Female) = 0.1. What does this now indicate about the causal relationships between gender, jogging and strokes? SEE NEXT PAGE 4 4AANB008 9. What is required for one sentence to be a syntactic consequence of some other sentences in propositional logic? What is required for it to be a semantic consequence of those sentences in propositional logic? Use this to explain the notions of soundness and completeness for propositional logic. 10. What does it mean to say that a theory for arithmetic is incomplete? Why is it not a contradiction to say that Gödel’s Theorem proves that a certain arithmetic sentence is unprovable, yet at the same time proves that it is true? FINAL PAGE 5