Full Idea
Rationality doesn't require consistency, because you can be rational despite undetected inconsistencies in beliefs, and it isn't always rational to respond to a discovery of inconsistency by dropping everything in favour of eliminating that inconsistency.
Gist of Idea
You can be rational with undetected or minor inconsistencies
Source
Gilbert Harman (Rationality [1995], 1.2)
Book Reference
Harman,Gilbert: 'Reasoning Meaning and Mind' [OUP 1999], p.22
A Reaction
This strikes me as being correct, and is (I am beginning to realise) a vital contribution made to our understanding by pragmatism. European thinking has been too keen on logic as the model of good reasoning.