Since this would be a rather uncharitable interpretation of Thaler and Sunstein, it seems most sensible to follow Hausman and Welch’s suggestion to broaden the definition so that it encompass all other types of incentives as well. Thus, they define a nudge as follows:
“Nudges are ways of influencing choice without limiting the choice set or making alternatives appreciably more costly in terms of time, trouble, social sanctions, and so forth”.