Full Idea
Many philosophers now concede that it is rational to accept a proposition not because we can directly verify it but because it is supported by considerations of simplicity, theoretical utility, explanatory power and/or intuitive plausibility.
Gist of Idea
We accept unverifiable propositions because of simplicity, utility, explanation and plausibility
Source
Joseph Melia (Modality [2003], Ch.5)
Book Reference
Melia,Joseph: 'Modality' [Acumen 2003], p.101
A Reaction
This suggests how the weakness of logical positivism may have led us to the concept of epistemic virtues (such as those listed), which are, of course, largely a matter of community consensus, just as the moral virtues are.