 According to Stich, roughly speaking, a physical system contains syntactically structured objects when two conditions are satisfied. First, there is a mapping between the behaviorally relevant physical states of the system and a class of syntactic types, which are specified by a grammar that defines how complex syntactic types can be formed out of (finitely many) primitive syntactic types. Second, the behavior of the system is explained by a theory whose generalizations are formulated in terms of formal relations between the syntactic types that map onto the physical states of the system.