In our taxonomy, we use the term `metatheory' in a slightly more inclusive sense than is standard. For us, the term covers (i) theorems establishing that a logical system has (or lacks) certain mathematical properties (the customary sense), as well as (ii) general discussions whose vocabulary includes terms making reference to logical systems and their mathematical properties. (Metatheory in the sense of (ii) may correspond to what Jon Doyle has called ``rational psychology'' (1988), the attempt to ``logicize'' the mind.) The discussion in (ii), of course, often includes straight metatheory from (i).