Adam Leite

Keith DeRose has recently argued that the contextual variability of appropriate assertion, together with the knowledge account of assertion, yields a direct argument that 'knows' is semantically context-sensitive. The argument fails because of an equivocation on the notion of warranted assertability. Once the equivocation is removed, it can be seen that the invariantist can retain the knowledge account of assertion and explain the contextual variability of appropriate assertion by appealing to Williamson's suggestion that practical and conversational considerations can influence the extent to which adherence to the constitutive norm of assertion matters.

Traditional epistemological reflection on our beliefs about the world attempts to proceed without presupposing or ineliminably depending upon any claims about the world. It has been argued that epistemological externalism fails to engage in the right way with the motivations for this project. I argue, however, that epistemological externalism satisfyingly undermines this project. If we accept the thesis that certain conditions other than the truth of one's belief must obtain in the world outside of one's mind in order for one to have knowledge (or justified belief) about the world, then there is no good intellectual motivation for taking up the traditional project. This results stands even if we accept the traditional theses that knowledge requires justified belief and that justified belief requires the ability to provide good reasons for one's belief.

In the broadest sense of the term, fallibilism is an anti-dogmatic intellectual stance or attitude: an openness to the possibility that one has made an error and an accompanying willingness to give a fair hearing to arguments that one’s belief is incorrect (no matter what that belief happens to be about). So understood, fallibilism’s central insight is that it is possible to remain open to new evidence and arguments while also reasonably treating an issue as settled for the purposes of current inquiry and action. Fallibilism, so construed, was given its most influential formulation – and its name – by C. S. Peirce, though it was advocated by earlier philosophers as well, particularly the later ancient skeptic Philo of Larissa and perhaps also Hume. Contemporary epistemologists almost universally agree in endorsing this intellectual stance; it is part of the undisputed framework within which contemporary epistemological theorizing takes place.

Guided by an account of the norms governing justificatory conversations, I propose that person-level epistemic justification is a matter of possessing a certain ability: the ability to provide objectively good reasons for one's belief by drawing upon considerations which one responsibly and correctly takes there to be no reason to doubt. On this view, justification requires responsible belief and is also objectively truth-conducive. The foundationalist doctrine of immediately justified beliefs is rejected, but so too is the thought that coherence in one's total belief system is sufficient, or indeed necessary, for justification. The problem of the regress is solved by exploiting the 'localist' idea that in order to possess the ability to justify any given belief, one only needs to be in a position to draw upon appropriate justified background beliefs to provide good reasons for holding the belief; one needn't be able to defend the relevant background beliefs, and so on, all at one sitting.

Modern-day heirs of the Cartesian revolution have been fascinated by the thought that one could utilize certain hypotheses – that one is dreaming, deceived by an evil demon, or a brain in a vat – to argue at one fell swoop that one does not know, is not justified in believing, or ought not believe most if not all of what one currently believes about the world. A good part of the interest and mystique of these discussions arises from the contention that the seeds of such arguments lie in our ordinary epistemic practices, so that external world skepticism can arise “from within”. But is this contention correct? I doubt it. Taking skepticism seriously requires that we address this question head on. To do so, I will approach skeptical arguments from a certain vantage point. I will try to stand, as far as possible, with both feet squarely in ordinary life. I will start out with all of our ordinary commitments about what is the case, about what we know or have reason to believe, about when someone knows, is justified, or has good reason to believe something, and about how one should proceed in deciding what to believe. My question, then, will be this. From within that vantage point can I somehow be moved in a reasonable way to accept the conclusion that I know far less about the world around me than I thought, or that epistemically speaking, I really ought not believe much of what I have believed about the world around me? In order for such movement to take place, I will have to find reason from within my ordinary standpoint to discount or reject much of what I ordinarily accept. And of course, that reason will have to come from some..

Traditional epistemological reflection on our beliefs about the world attempts to proceed without presupposing or ineliminably depending upon any claims about the world. It has been argued that epistemological externalism fails to engage in the right way with the motivations for this project. I argue, however, that epistemological externalism satisfyingly undermines this project. If we accept the thesis that certain conditions other than the truth of one's belief must obtain in the world outside of one's mind in order for one to have knowledge (or justified belief) about the world, then there is no good intellectual motivation for taking up the traditional project. This results stands even if we accept the traditional theses that knowledge requires justified belief and that justified belief requires the ability to provide good reasons for one's belief.