An Essay in the Metaphysics of Propositions
University Press 2012
Propositions are key players in philosophy of language and mind. Roughly speaking, they are abstract repositories of meaning and truth. More specifically, they are the semantic values of truth-evaluable sentences; they are the objects of belief, desire and other propositional attitudes; they are what we agree and disagree about in conversation, and they are what is communicated in successful discourse. By philosophical tradition, propositions have their truth values eternally; that is, they always include a reference to a time as a component, and if true, they are always true. The proposition expressed in English by the sentence It is raining in Malta is more completely expressed by something like It is raining in Malta at noon local time on May 4, 2013. This standard view is called eternalism. In her new book Transient Truths: An Essay in the Metaphysics of Propositions (Oxford University Press, 2012), Berit Brogaard, associate professor of philosophy and psychology at the University of Missouri at St. Louis, calls this traditional view into question. Brogaard defends temporalism, the claim that some propositions do not have their truth values eternally – they lack a time-stamp. She argues instead that eternalists cannot adequately explain how we retain beliefs over time, how we modify beliefs, and how we agree and disagree over the span of an ordinary conversation, and she presents a new argument for temporalism from the phenomenology of conscious mental states. Her lucid and comprehensive discussion is a milestone in debates about our experience of time as expressed in natural language.