 (For surveys of this literature see Kärkkäinen 2007; Olson and Hall 2002, 95–115; Peters 1993, 103–45.) These writers are often unclear about what Trinity theory they’re endorsing. The views seem to range from tritheism, to the idea that the Trinity is an event, to something that differs only slightly, or only in emphasis, from pro-Nicene or one-self theories (see section  1  and section  3.3  of the supplementary document on the history of trinitarian doctrines). Merricks observes that some views advertised as “social trinitarianism” make it “sound equivalent to the thesis that the Doctrine of the Trinity is true but modalism is false” (Merricks 2006, 306). However, a number of Christian philosophers, and some theologians employing the methods of analytic philosophy, have started with this literature and then proceeded to develop relatively clear three-self Trinity theories, which are surveyed here. They differ in how they attempt to secure monotheism (Leftow 1999). There are many such Trinity theories, and it is not clear that all the options have yet been explored (Davidson 2016).