** Next:** About this document ...

# Pollock Part II

**Selmer Bringsjord
**

Philosophy of AI

- Back Up to the Problem of Ordinary Non-Defeasible Inference
- Suppositional Reasoning

** Lottery Paradox Diagnosis**

Since we ought never to believe both *p* and ,
and since we *know* that a certain ticket *will* win,
we must conclude (since the reasoning itself is unexceptionable)
that it's not the case that we ought to believe that *t*_{k} will
win. We must replace this belief with a defeasible belief based
on that fact that we have but a *prima facie* reason for
believing that *t*_{k} will win.

** Lottery Paradox Case of Collective Defeat**

Suppose that we are warranted in believing *r* and that we have
equally good prima facie reasons for

where
is inconsistent but no
proper subset of
is inconsistent with *r*.
Then, for every *p*_{i}:

In this case we have equally strong support for each *p*_{i} and each
,
so they collectively defeat one another.

** The Paradox of the Preface**

** Next:** About this document ...
*Selmer Bringsjord*

*2000-11-27*