 Finally, one of the more productive developments of virtue ethics has come through the study of particular virtues and vices. There are now a number of careful studies of the cardinal virtues and capital vices (Pieper 1966; Taylor 2006; Curzer 2012; Timpe and Boyd 2014). Others have explored less widely discussed virtues or vices, such as civility, decency, truthfulness, ambition, and meekness (Calhoun 2000; Kekes 2002; Williams 2002; and Pettigrove 2007 and 2012). One of the questions these studies raise is “How many virtues are there?” A second is, “How are these virtues related to one another?” Some virtue ethicists have been happy to work on the assumption that there is no principled reason for limiting the number of virtues and plenty of reason for positing a plurality of them (Swanton 2003; Battaly 2015). Others have been concerned that such an open-handed approach to the virtues will make it difficult for virtue ethicists to come up with an adequate account of right action or deal with the conflict problem discussed above. Dan Russell has proposed cardinality and a version of the unity thesis as a solution to what he calls “the enumeration problem” (the problem of too many virtues). The apparent proliferation of virtues can be significantly reduced if we group virtues together with some being cardinal and others subordinate extensions of those cardinal virtues. Possible conflicts between the remaining virtues can then be managed if they are tied together in some way as part of a unified whole (Russell 2009). This highlights two important avenues for future research, one of which explores individual virtues and the other of which analyses how they might be related to one another.