 The issues at stake between serious counterpart theory and transworld identity become complex quickly. The tangle of considerations can be more formally motivated than are the intuitive considerations already canvassed. Your theory might force unwelcome baroqueness in expression, when formalized (Linsky and Zalta 1996; Williamson 2000; 2002). Worse, you might find that you cannot even say in the preferred formal language what you want, intuitively, to say: e.g., “There could have been things that do not actually exist” (Russell discusses the history of this example: 2013, p. 485).