The other day when I was lecturing on Souriau and Latour's notion of "instauration" someone asked me whether we can help bringing about something by claiming that it doesn't exist. Today we considered the issue of bringing things about in connection to some solutions to the Plato's beard aporia. Take Latour's conception of truth: it is not that something holds because it is true but rather that something it is true because it holds. It gets interesting if we consider what we do when we, say, write fiction. We can say that fiction we provide descriptions associated with characters and go in some length in the direction of making them credible. Consider, for instance, Russell's theory of descriptions. We can say that by writing fiction (and providing descriptions for, say, Sherlock Holmes or Gregor Samsa) we do everything humans can do with bare language to make something (like a person) exist. We don't go further, the characters don't cross a threshold, a further test of force that makes them exist. Fictions, then, are just a matter of descriptions - they hold but not enough. They are false, as Russell would have.
This threshold of existence can be also understood in terms of borders between modes of existence, in the plurirealist way. In any case, the threshold seems to provide some measure of independence with respect to the descriptions. Fiction is description-dependent. This is the challenge for our (6 months) old Millnong project. Fiction is a negotiation among humans only (or, rather, humans mostly, as surely there is a fauna in the text and in the brain that has to cooperate). The threshold - a threshold of a test of force - ushers in what holds by a stronger alliance.