Will_Sawin comments on Conceptual Analysis and Moral Theory - Less Wrong

60 Post author: lukeprog 16 May 2011 06:28AM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Article Navigation

Comments (456)
Tags: metaethics morality

Comments (456)

You are viewing a single comment's thread. Show more comments above.

Comment author: Oscar_Cunningham 16 May 2011 11:56:23AM *  4 points [-]

PS: Very Tarskian and Bayesian of them, but are you sure they didn't say, "A belief in X is knowledge if one would never have it whenever not-X"?

I'm thinking of Robert Nozick's definition. He states his definition thus:

  1. P is true
  2. S believes that P
  3. If it were the case that (not-P), S would not believe that P
  4. If it were the case that P, S would believe that P

(I failed to remember condition 1, since 2 & 3 => 1 anyway)

Comment author: Will_Sawin 16 May 2011 04:11:54PM 4 points [-]

A different objection, following Eliezer's PS, is that:

Between me and a red box, there is a wall with a hole. I see the red box through the hole, and therefore know that the box is red. I reason, however, that I might have instead chosen to sit somewhere else, and I would not have been able to see the red box through the hole, and would not believe that the box is red.

Or more formally: If I know P, then I know (P or Q) for all Q, but:

P => Believes (P)

does not imply

(P v Q) => Believes (P v Q)

Comment author: Tyrrell_McAllister 16 May 2011 04:35:54PM *  0 points [-]

Between me and a red box, there is a wall with a hole. I see the red box through the hole, and therefore know that the box is red. I reason, however, that I might have instead chosen to sit somewhere else, and I would not have been able to see the red box through the hole, and would not believe that the box is red.

This is a more realistic, and hence better, version of the counterexample that I gave in my ETA to this comment.

Powered by Reddit Powered by Reddit