 It is a law in many logical systems, The Indiscernibility of Identicals, that things that are identical share all of their properties. The controversial converse, The Identity of Indiscernibles, says that things that share all of their properties are identical. If “property” is understood sufficiently liberally, then the latter principle is certainly true—any object b has the property of “being identical to b”, and if c also has that property then \(b = c\). The question is whether the principle holds with any more restricted sense of property. Ladyman et al.(2012) discuss and relate different interpretations of indiscernibility associated with various senses of properties. Many of these interpretations would ground different versions of the identity of indiscernibles principle. (See the entry on this principle for philosophical perspectives other than those considered by Ladyman et al.(2012).) 