Whereas with a Centred Set Perspective it is difficult, if not impossible, for anyone, apart from Christ, to judge whether anyone, except themselves, is in or out. Now this kind of fuzzy logic drives Christians crazy. So to deal with the fuzziness Christians have tried to incorporate Centred Set Christi-Anarchy, as a subset, into Closed Set Christianity. Discipleship is a Centred Set. To be a disciple is to be constantly moving toward the centre, which is Christ.
Boundaries do exist.
There is a boundary that sets the standard. One is either in Christ, or not in Christ. Dominant Paradigm - Closed Set Christianity ii.