Ernest Sosa

According to the main tradition, knowledge is either direct or indirect: direct when it intuits some perfectly obvious fact of introspection or a priori necessity; indirect when based on deductive proof stemming ultimately from intuited premises. Simple and compelling though it is, this Cartesian conception of knowledge must be surmounted to avoid skepticism. Seeing that the straight and narrow of deductive proof leads nowhere, C. I. Lewis wisely opts for a highroad of probabilistic inference. But how can one arrive at a realm inaccessible through direct knowledge having set out from one thus accessible? How could probabilistic inference offer any help? There are two different answers to these questions in Lewis's writings, and he moves from one to the other under pressure of well known objections from perceptual relativity. Our action divides into three acts, which we review in turn.

In what way is knowledge better than merely true belief? That is a problem posed in Plato’s Meno. A belief that falls short of knowledge seems thereby inferior. It is better to know than to get it wrong, of course, and also better than to get it right by luck rather than competence. But how can that be so, if a true belief will provide the same benefits? In order to get to Larissa you do not need to know the way. A true belief will get you there just as well. Is it really always better to know the answer to a question than to get it right by luck? In part i we ponder: Is knowledge always better at least in epistemic respects? The affirmative answer is subject to doubts deriving from a conception of belief as sufficient confidence, but is defensible against such doubts. In our search for the special value of knowledge, we then explore in part ii the relation between knowledge and proper action. Part iii goes on to consider how the value of knowledge intuition acquires further interest through its equivalence with the view of knowledge as a norm of assertion. Finally, part iv steps back to examine what we might mean in saying that to know is always, necessarily better than to get it right by luck while really in ignorance. In order to defend our value-of-knowledge intuition we need first to understand it more clearly. Part iv offers an explanation.

The received definition of knowledge (as true, evident belief) has recently been questioned by Edmund Gettier with an example whose principle is as follows. A proposition, p, is both evident to and accepted by someone S, who sees that its truth entails (would entail) (that either p is true or q is true). This last is thereby made evident to him, and he accepts it, but it happens to be true only because q is true, since p is in fact false. Hence, inasmuch as he has no evidence for the proposition q, S can hardly be said to know (that either p is true or q is true). Here then is a formula for true, evident beliefs that are not cases of knowledge. I discuss the possibility of adding a fourth condition to this triad.