money. Empirical research has demonstrated that when group membership is made salient and known to both parties, trust is granted more readily to in-group members than out-group members. This occurred even when the in-group stereotype was comparatively less positive than an out-group's (e.g. psychology versus nursing majors), in the absence of personal identity cues, and when participants had the option of a sure sum of money (i.e. in essence opting out of the need to trust a stranger). In contrast, when only the recipient was made aware of group membership, trust becomes reliant upon group stereotypes. The group with the more positive stereotype was trusted (e.g. one's university affiliation over another) even over that of the in-group (e.g. nursing over psychology majors). Another reason for in-groups favoring behaviors in trust could be attributed to the need to maintain in-group positive distinctiveness, particularly in the presence of social identity threat. Trust in out-group strangers increased when personal cues to identity were revealed. Philosophy Whilst many philosophers have written about different forms of trust, most would agree interpersonal trust is the foundation on which these forms can be modeled. For an act to be classed as an expression of trust, it must not betray the expectations of the trustee. In this sense, some philosophers such as Lagerspetz argue that trust is a kind of reliance, though not merely reliance. Gambetta argued it is the inherent belief that others generally have good intentions which is the foundation for our reliance on them. Philosophers such as Annette Baier have contended this view, establishing a difference between trust and reliance by saying that trust can be betrayed, whilst reliance can only be disappointed (Baier 1986, 235). Carolyn McLeod explains Baier's argument by giving the following examples: we can rely on our clock to give the time, but we do not feel betrayed when it breaks, thus, we cannot say that we trusted it; we are not trusting when we are suspicious of the other person, because this is in fact an expression of distrust (McLeod 2006). The violation of trust warrants this sense of betrayal. Thus, trust is different from reliance in the sense that a trustor accepts the risk of being betrayed. Karen Jones proposed that there is an emotional aspect to trust, an element of optimism that the trustee will do the right thing by the trustor, also described as affective trust. Though,