The Beauty of Understanding: Aesthetic Methods of Theory Evaluation

Philosophers use a variety of methods to evaluate theories, theories that are sources of greater understanding. My dissertation argues that judgments of beauty are a justified part of how we evaluate theories. That is, I argue that beauty is part of what makes a philosophical theory better. I reach this conclusion by analyzing two powerful and popular methods of theory evaluation: reflective equilibrium and simplicity. The literatures on both reflective equilibrium and simplicity clarify how these methods work and why they are justified methods of theory evaluation. But I argue that the going accounts of reflective equilibrium and simplicity have gaps remaining. Both methods rely on judgments that are unexplained. Reflective equilibrium requires judgments of coherence and simplicity requires judgments of simplicity. Yet the going accounts give no explanation of how to make these judgments. I argue that these gaps are best filled by identifying judgments of coherence and judgments of simplicity as species of judgments of beauty. Judgments of coherence and simplicity should be identified as species of judgments of beauty because they share a special character as unprincipled, yet genuine, judgments. That is, all three kinds of judgment are not made by reference to principles, and yet reasonable, nonarbitrary judgments are possible. This identification completes the accounts of reflective equilibrium and simplicity because it explains how we make judgments of coherence and simplicity, despite lacking a principled account of those judgments. This means that two powerful and popular methods of theory evaluation do in fact use judgments of beauty to identify better theories. I conclude by arguing that using judgments of beauty to identify better theories is justified because of the fundamental role these judgments play in guiding theory evaluation.