Find all members of the class which we know about and sort them by an appropriate property.   @@ Move to library
function (c) {
      var sortBy = kb.sym({
        'http://www.w3.org/2005/01/wf/flow#Task': 'http://purl.org/dc/elements/1.1/created',
        'http://www.w3.org/ns/pim/trip#Trip': // @@ put this into the ontologies
        'http://www.w3.org/2002/12/cal/ical#dtstart',
        'http://www.w3.org/2000/10/swap/pim/qif#Transaction': 'http://www.w3.org/2000/10/swap/pim/qif#date',
        'http://www.w3.org/2000/10/swap/pim/qif#SupportingDocument': 'http://purl.org/dc/elements/1.1/date'}[subject.uri])

      if (!sortBy) {
        sortBy = kb.any(subject, UI.ns.ui('sortBy'))
      }
      return sortBy
    }