- What is metaphysics, precisely?
- How is one epistemically justified in believing a claim that is part of a metaphysical theory?
- How are metaphysics and science epistemically related? Put another way, do claims in one field enter into an implication relation with claims in the other field?
- Is there an epistemic procedure in metaphysics, as there is to some degree in science (i.e. scientific method).
- How does one decide between competing metaphysical theories?
My project is to answer questions like these. I will do so by developing a theory of epistemic justification with respect to beliefs in metaphysical propositions. Metaphysical propositions are those that are at least implicitly agreed by self-identifying professional metaphysicians to constitute the subject matter of metaphysics. I will investigate the sorts of things that might go into the conferral of epistemic justification on beliefs of metaphysical propositions. I'll also investigate what sorts of things might defeat said justification. The plan is as follows.
The first chapter deals with intuitions and beliefs in metaphysical propositions. What are intuitions? In this chapter I go over the literature on intuitions and provide some commentary on what I take intuitions to be which will then be useful for understanding how beliefs in metaphysics are justified. I show how intuition can confer at least prima facie justification on beliefs in metaphysical propositions. I also respond to skeptics about intuition and its justificatory role in metaphysics.
The second chapter is about the relationship between metaphysics and science. In many discussion, there is an implicit assumption that a prima facie justified belief in a metaphysical proposition can be defeated by a well supported claim in science that is somehow not compatible with the aforementioned belief. I look further into what this assumption is all about. Does science have epistemic priority over metaphysics? Can any claim in science serve as a potential defeater for a metaphysical belief? Does relationship work the other way around, i.e. can claims in metaphysics defeat justification for scientific beliefs? Why or why not?
In the third chapter, I discuss the phenomenon of competing theories. Suppose that you have two theories that make logically incompatible claims. Both are supported by intuition and both are compatible with our best science. How do you decide between these two theories? A popular move that theorists make is to appeal to what are called "theoretical virtues." Theoretical virtues are properties that theories possess that supposedly make them more likely to be truth conducive. Examples of theoretical virtues include simplicity, explanatory power, fruitfulness for further research, fit with previous theories, etc. Are these sorts of properties really truth conducive? If so, how? The focus of this chapter will be a further exploration of these virtues, and how they might be used in order to break ties between competing theories.
(The foregoing three chapters constitute the core of my dissertation. Later chapters will be mainly about tying loose ends, such as applications, considering certain key objections, and generalizing this approach to other areas in philosophy. Once it becomes clearer what I'll be doing in these later chapters, I'll update this dissertation abstract.)