## Miracles, trust, and ennui in Barnes' Predictivism

Published in Logos&Episteme, March 2011. An earlier version of this paper was presented as part of an author-meets-critics symposium at the 2010 Philosophy of Science Assocation meeting in Montreal.

### Abstract

Eric Barnes' The Paradox of Predictivism is concerned primarily with two facts: predictivism (the fact that novel predictions play an important part in scientific confirmation) and pluralism (the fact that scientific development is not just a matter of isolated individuals judging the truth, but at least partly a matter of trusting legitimate experts). In the middle part of the book, he peers through these two lenses at the tired realist scarecrow of the no-miracles argument. He attempts to reanimate this weather-worn realist argument, contra suggestions by people like me that it should be abandoned. In this paper, I want to get clear on Barnes' contribution to the debate. He focuses on what he calls the miraculous endorsement argument, which explains not the success of a specific theory but instead the history of successes for an entire research program. The history of successes is explained by reliable and improving methods, which are the flipside of approximately true background theories. Yet, as Barnes notes, the whole story must begin with methods that are at least minimally reliable. Barnes demands that the realist explain the origin of the minimally reliable take-off point, and he suggests a way that the realist might do so. I contend that his explanation still relies on contingent developments and so fails to completely explain the development of take-off theories. However, this line of argument digs into familiar details of the no-miracles argument and overlooks what's new in Barnes' approach. By calling attention to pluralism, he reminds us that we need an account of scientific expertise. This is important, I suggest, because expertise is not indefinite. We do not trust specific experts for everything, but only for things within the bounds of their expertise. Drawing these boundaries relies on our own background theories and is only likely to be reliable if our background theories are approximately true. I argue, then, that pluralism gives us reason to be realists.

@ARTICLE(Magnus2011,
AUTHOR = {P.D. Magnus},
TITLE = {Miracles, trust, and ennui in {B}arnes' \emph{Predictivism}},
JOURNAL = {Logos\&Episteme},
VOLUME = {2},
NUMBER = {1},
YEAR = {2011},
MONTH = mar,
PAGES = {103--115}
)