 In the discussion of transworld identity in the 1960s and 1970s (when the issue came to prominence as a result of developments in modal logic), it was debated whether the notion of transworld identity is genuinely problematic, or whether, on the contrary, the alleged ‘problem of transworld identity’ is merely a pseudo-problem. (See Loux 1979, Introduction, Section III; Plantinga 1973 and 1974, Ch. 6; Kripke 1980 (cf. Kripke 1972); Kaplan 1967/1979; Kaplan 1975; Chisholm 1967; for further discussion see, for example, Divers 2002, Ch. 16; Hughes 2004, Ch. 3; van Inwagen 1985; Lewis 1986, Ch. 4.)