Vagueness in a Precise World: Essays on Metaphysical Vagueness.

Abstract

Our words are vague, yet the world is precise. This dissertation consists of three essays that jointly attempt to articulate, explore, and defend this claim.

In the first essay, I present my positive proposal for a non-metaphysical treatment of vagueness. Inspired by research on the Problem of the Many, I claim that we are speaking many perfectly precise languages simultaneously and that each speech act involves uttering many perfectly precise sentences. This position, which I call supersententialism, is the most plausible alternative to metaphysical vagueness: it provides a fully reductive account of vagueness that preserves the T-schema.

The second essay aims to address a rampant, albeit unnoticed, argument schema that purports to show that non-metaphysical accounts of vagueness cannot explain vagueness in fundamental, or perfectly natural, properties. In response, I propose a position that I call ersatz metaphysical vagueness according to which the term ‘perfectly natural’ is vague. Ersatz metaphysical vagueness retains the idea that the world is precise, but replicates the advantages of genuine metaphysical vagueness. I show how, by adopting this hypothesis, there can be vagueness in attributions of perfectly natural properties arising from the vagueness in our notion of perfect naturalness rather than from ‘the world itself’. Ersatz metaphysical vagueness thus provides us with a highly general alternative to genuine metaphysical vagueness.

The final essay explores the relationship between metaphysical vagueness and ontological deflationism. Ontological deflationist positions treat the quantifier as having a highly plastic meaning. This plasticity naturally leads to vagueness in the quantifier. Thus, ontological deflationists are committed to vague existence. Is this vague existence ‘metaphysical vagueness’ or ‘vagueness in the world’? The rest of the essay clarifies this question and answers it under various clarifications.