Outright Belief

What is the relation between (a) “full” or “outright” belief and (b) the various levels of confidence that agents can have in the propositions that concern them? This paper argues for a new answer to this question. Decision theory implies that in making decisions, rational agents must treat certain propositions as though they were completely certain; but on most forms of decision theory, these propositions are not ones for which any finite agent could have maximal justification – the agent will clearly have less justification for these propositions than for elementary logical truths. Thus, every adequate model of a finite rational agent’s belief-system must involve two set of credences – theoretical credences (the belief-states that keep track of how much justification the agent has for the propositions in question) and practical credences (the belief-states on which the agent bases on her practical decisions). A full or outright belief in p can be defined as the state of being stably disposed to assign a practical credence of 1 to p, for all normal practical purposes. This definition allows for a kind of reconciliation between the pragmatist and intellectualist approaches in epistemology. 1. Outright belief and levels of confidence Sometimes, we think of belief as a phenomenon that comes in degrees – that is, as consisting in the many different levels of confidence that an agent might have in various propositions. Sometimes, we think of belief as a simple two-place relation that holds between an agent and a proposition – that is, as what I shall here call outright belief. Both ways of thinking of belief seem to be in evidence in everyday folk-psychological discourse. It is perfectly natural to say, for example, you are considerably more confident that Dublin is the capital of Ireland than that Dushanbe is the capital of Tajikistan. But it is also † University of Southern California, School of Philosophy, 3709 Trousdale Parkway, Los Angeles, CA 90089-0451, USA, Email: [email protected]