Full Idea
The pragmatist view is that all our theories are instrumental, are mental modes of adaptation to reality, rather than revelations or gnostic answers to some divinely instituted world enigma.
Clarification
'gnostic' here means 'spiritual knowledge'
Gist of Idea
Pragmatism says all theories are instrumental - that is, mental modes of adaptation to reality
Source
William James (Pragmatism - eight lectures [1907], Lec 5)
Book Reference
James,William: 'Pragmatism - eight lectures' [Dover 1995], p.74
A Reaction
This treats instrumentalism as the pragmatic idea of theories as what works (and nothing more), with, presumably, no interest in grasping something called 'reality'. Presumably instrumentalism might have other motivations - such as fun.