Day 4: The Gettier Critique

•     The Traditional Analysis

•     The Gettier Critique

•     Complete Justification Reply to Gettier

•     Skepticism and Knowledge

•     An Indefeasibility Analysis

•     Please Read IE 66-77 (part independent study).

The Traditional Analysis

•    S knows that p if, and only if,

   (1) S believes p;

   (2) p is true, and

   (3) S is justified in believing p.

The Gettier Critique

•    Gettier’s examples

•    Some other examples

•    Do these examples undermine the account of knowledge given in the Meno?

Complete Justification Reply to Gettier

•    What is the complete justification reply?

•    What are the possible concerns with this reply?

Skepticism and Knowledge

•      N. Everitt & A. Fisher (Modern Epistemology, 1995) argue as follows:

    (1) Any analysis of knowledge should capture a significant part of its common usage.

    (2) It’s part of the common usage of “knowledge” that we know many things, that skepticism is not true or cannot be taken seriously.

    (3) If we add complete justification to the analysis of knowledge, it follows almost immediately that there is very little we can know (a form of skepticism).

    (4) Therefore, complete justification cannot be part of the analysis of knowledge.

Skepticism and Knowledge

•      Critical reworking of EF’s Argument:

    (1) Any analysis of knowledge should capture a significant part of its usage in a range of discussions, including philosophical.

    (2) Many of the arguments between skeptics and non-skeptics are interesting and non-trivial.  This suggests that neither skepticism nor anti-skepticism follows almost immediate from the definition of knowledge.

    (3) If we add complete justification to the definition of knowledge, it follows almost immediately that there is very little we can know (a form of skepticism).

    (4) Therefore, complete justification cannot be part of the analysis of knowledge.

Skepticism and Knowledge

•     EF’s argument and the Critical Reworking have the same conclusion

•     EF’s argument commits them to the rejection of skepticism, but the Critical Reworking has no such commitment

•     Worries/limits of the Critical Reworking?

An Indefeasiblity Analysis

•      S knows that p at t₁ iff

   (i)   p is true;

   (ii)  S believes that p at t₁;

   (iii) p is evident to S at t₁;

   (iv)  there is no true proposition such that if it became evident to S at t₁, p would no longer be evident to S.

From Klein, Peter, “A Proposed Definition of Propositional Knowledge,” The Journal of Philosophy 68, 16 (1971), pp. 471-482.

An Indefeasiblity Analysis

•     What does “evident” (borrowed from Roderick Chisholm) mean?

•     What does “indefeasibility” mean?

•     Indefeasibility condition deals with Gettier problems

•     The sense in which Klein’s Analysis is neutral on skepticism vs anti-skepticism