 The model of a space of possible outcomes of a throw of a die gives us an initial idea of what the distinctive properties of state of affairs are and why it is plausible to assume that there are any states of affairs. It leaves questions about the precise nature of states of affairs open. For example, Wittgenstein (1918: 4.26) argued that only elementary sentences “picture” states of affairs. An elementary sentence in Wittgenstein’s sense is a concatenation of simple proper names each of which refers to a simple object. The names in the elementary proposition are arranged in a way that can be mapped onto an arrangement of the simple objects named. This arrangement of objects is the state of affairs pictured by the elementary sentence. Nothing said so far rules out that states of affairs that involve some objects and properties (relations) combine to form further complex states of affairs that have states of affairs as constituents. (Pollock 1984a: 55–6) defines negation, conjunction etc. for states of affairs. For example, if there is a state of affairs \(S_1\) and a state of affairs \(S_2\), their conjunction is the state of affairs that obtains if, and only if, both \(S_1\) and \(S_2\) obtain. If one wants to restrict the space of possible states to combinations of simple objects, one needs to marshal arguments that show that this and similar conceptions of complex states of affairs is flawed. (This entry is mainly concerned with simple states of affairs.)