During the 2016 United States campaign, the presidential and the vice presidential candidates of the Democratic Party both suffered from trust deficits. After decades of scandals and pseudo-scandals, two thirds of registered voters told pollsters that they did not trust Hillary Clinton. Her running mate, Senator Tim Kaine, was also the object of skepticism from Democratic voters because of his religiously motivated opposition to abortion (though not to abortion rights).
The morning after Clinton accepted her party’s nomination, The New York Times ran a story with the headline, “Hillary Clinton Asks Not for Trust, but for Faith in Her Competence.” As philosophers since Annette Baier (1986; see also Jones 1999) have argued, trusting someone involves judging or feeling that they are competent (in the domain of trust) and bear you goodwill. The Times headline suggests that Clinton may have given up on the second component of trust, but not everyone seeking to make her president abandoned that goal. Michelle Obama, in a speech at the nominating convention, said, “I trust Hillary Clinton to lead this country.” Likewise, Bernie Sanders – her main opponent in the nominating contest – gave her his full-throated endorsement. One of Sanders’s delegates at the convention, John Ferguson, told reporters that, although he was initially reluctant to support Clinton, that endorsement had changed his mind: “If he trusts her, I trust her.” Such a vouching gambit was also used to coax people to support Kaine. For instance, Ilyse Hogue, the president of NARAL Pro-Choice America, wrote in a public post on Facebook, “I believe [Clinton] chose Tim Kaine because she trusts the guy, and I trust her.”
How is this gambit meant to work? To answer this question, we need to reflect on what I’ll call the topology of trust. Think of individual people as nodes in a directed network, where an edge from node A to node B represents A’s trusting B. Three of the most important properties in such a network are reflexivity (trusting yourself), symmetry (being trusted by those you trust), and transitivity (trusting those who are trusted by those you trust). The gambit relies on the (apparent) rationality of extending trust transitively. That is, the gambit works to the extent that people treat the fact that someone they trust trusts someone as a reason to trust that person as well. If I trust Bernie Sanders to be a good US elected official and Bernie Sanders trusts Hillary Clinton to be a good US elected official, then I have a reason to trust Hillary Clinton to be a good US elected official. If I trust Hillary Clinton to be a good US elected official and Hillary Clinton trusts Tim Kaine to be a good US elected official, then I have a reason to trust Tim Kaine to be a good US elected official. So if I trust Sanders, Sanders trusts Clinton, and Clinton trusts Kaine, then I have a second-order reason to trust Kaine. That is to say, I have a reason to do something (trust Clinton) that will give me a reason to do another thing (trust Kaine).
These reasons needn’t be compelling. I can withhold my trust from Clinton even as I give it to people who trust her. I can withhold my trust from Kaine even as I give it to people who trust him. My hypothesis here is only that transitivity provides a pro tanto reason to extend trust, not an all-things-considered reason. Why would it do so? There are two arguments, one for each component of trust (competence and goodwill).
First, competence in a domain is highly associated with meta-competence in making judgments about competence in that domain (Collins & Evans 2007, chapter 2). Pianists are better than the average person at judging the expertise of pianists. Medical doctors are better than the average person at judging the expertise of medical doctors. If I trust Bernie Sanders to be a good US elected official, that means I deem him competent or even expert in the domain of US politics. It stands to reason, then, that I should expect him to be better than the average person at judging the competence of others in the domain of US politics. So if he gives his trust to Clinton, I have a reason to think that she would be competent.
Second, it’s psychologically difficult and perhaps even practically irrational to consciously engage in efforts to undermine your own values in the very process of pursuing and promoting those values. Imagine someone locking a door while they’re trying to walk through the doorway. Someone could do this by mistake, as a gag, or in pretense, but it’s hard to envision a case in which someone does this consciously. Likewise, it’s hard to envision a case in which someone genuinely bears you goodwill, and consciously expresses that goodwill by recommending that you put your fate in the hands of someone they expect to betray your trust. They might do so by mistake, as a gag, or in pretense, but a straightforward case is difficult to imagine. If I trust Bernie Sanders to be a good US elected official, that means I judge that he bears me relevant goodwill. It stands to reason, then, that I should expect him to act on that goodwill in a practically rational way. So if he gives his trust to Clinton, I have a reason to think that she would act consistently with his goodwill.
Putting these together, if I trust Sanders and he trusts Clinton, then I have a reason to think that she is politically competent and either bears me goodwill or at least would act in a way that’s consistent with bearing me goodwill. In other words, I have pro tanto reasons to trust her. Suppose I reject those reasons because I have already made my mind up about either Clinton’s competence or her goodwill. In that case, Sanders decision to trust her now gives me a reason to withdraw my trust from him. Either he is not such a good judge of political competence after all, or he doesn’t bear me the goodwill I thought he bore me. The transitivity of trust cuts both ways. If I refuse to extend my trust, I gain a reason to withdraw it from the first-order trustee. Indeed, during the 2016 election, we have seen precisely this phenomenon at work. Sanders’s own supporters booed him when he endorsed Clinton, and some yelled “We trusted you!” at Senator Elizabeth Warren when she did the same.
Baier, A. (1986). Trust and antitrust. Ethics, 96: 231-60.
Collins, H. & Evans, R. (2007). Rethinking Expertise. University of Chicago Press.
Jones, K. (1999). Second-hand moral knowledge. Journal of Philosophy, 96(2): 55-78.
Manne, K. 2014). Internalism about reasons: Sad but true? Philosophical Studies, 167(1): 89-117.
Raz, J. (1990). Practical Reason and Norms. Princeton University Press.
 https://assets.documentcloud.org/documents/2993809/The-New-York-Times-CBS-Poll.pdf. Accessed 29 July 2016.
 http://www.nytimes.com/2016/07/29/us/politics/hillary-clinton-democratic-nominee.html. Accessed 29 July 2016.
 https://www.facebook.com/ilyse.hogue/posts/10157276856155613. Accessed 29 July 2016.
 I am not going to take a stand here on the debate between reasons externalists and reasons internalists, so I’ll use someone’s having a reason to do something and there being a reason for someone to do something interchangeably. So far as I can tell, in this context, it doesn’t make a difference. For a recent perspective on this debate, see Manne (2014).
 For more on the notion of a second-order reason, see Raz (1990).
 http://www.nytimes.com/2016/07/26/us/politics/dnc-speakers-protests-sanders.html. Accessed 29 July 2016.