Contained in this dissertation are four essays on epistemology and logic. They are self-standing essays and can be read independently from one another. However, I think there are a few common themes that run throughout. Here I will briefly highlight one.
In the first chapter I discuss the principle of indifference: if a body of evidence E supports p no more than it supports q, and likewise E supports q no more than it supports p, then one's credence in p ought to be equal to one's credence in q. One feature of this principle is that it can be employed in the absence of any evidence regarding p and q. If one has no evidence bearing on p and q, then one's evidence supports them equally. Call principles like these 'something-from-nothing principles'. Something-from-nothing principles are evidential principles that govern rational credences and beliefs in cases where has a substantial lack of evidence and background information.
One theme in this dissertation is the idea that something-from-nothing principles are problematic. In the first chapter, I defend an argument that the principle of indifference is inconsistent, and I show that a similar something-from-nothing principle in the imprecise confidence model is problematic. In the second chapter I motivate and defend a no-rules theory of induction. Hume's `project the past into the future' is a something-from-nothing principle, and, focusing on Roger White's portrayal of this style of induction, I argue that the principle should be rejected.
Something-from-nothing principles principles are usually taken to be knowable a priori. If they are applicable in cases where one has no evidence or empirical knowledge relevant to the use of the principle, then one must be in a position to know that the principle is true in such cases. The general picture of evidential relations suggested by the no-rules account of induction defended in chapter 2 undermines the idea that evidential principles are knowable a priori. In chapter 3 and 4 I discuss normality theories of knowledge and justification and I claim that it is natural for normality theorists to find something-from-nothing principles problematic
