Assertion: gratitude | /r/HasProperty | viewed as social and civic virtue
Facets:
value: variously
type: DEGREE
value: historically
type: TEMPORAL
Source sentences:
text: Historically, gratitude has been viewed variously as a social and civic virtue, a motivator of benevolence and both a cognitive and emotional reminder of the social need to reciprocate (Emmons, McCullough, Tsang, 2003).