Full Idea
The main difficulty with instrumentalism is its implausible account ot the meaning of theoretical claims and concepts. Most scientists take them to be straightforward attempts to describe the world. Most say they are useful because they are accurate.
Gist of Idea
For most scientists their concepts are not just useful, but are meant to be true and accurate
Source
Geoffrey Gorham (Philosophy of Science [2009], 4)
Book Reference
Gorham,Geoffrey: 'Philosophy of Science' [One World 2009], p.103
A Reaction
Instrumentalism is seen as a Pragmatist view, and Dewey is cited.