“…The idea of content parthood has been studied by logicians normally in a logic for analytic containment. See, e.g.,Angell (1989),Correia (2004),Fine (2016),Elgin (2020).Russell (1918: 37ff., 47ff.) andWittgenstein (1921: 4.21, 4.221, 4.51, 5, 5.01, 5.3) also drew a similar distinction among propositions.…”