1. Locke ([1690] 1974).
2. Baillie (1993, p. 193); Parfit (1984, p. 202).
3. Noonan (1989, p. 2).
4. I am referring to that aspect of Leibniz’ identity definition according to which identity is a relation an object can bear only to itself.
5. E.g. Butler ([1736] 1975); Reid ([1785] 1941); Swinburne (1973, 1976, 1984); Chisholm (1976); Madell (1981, 1985, 1986, 1988).