Although published mostly in the form of short, terse essays that do not explicitly rely on any overriding theory, his work is nonetheless noted for a highly unified character, the same methods and ideas brought to bear on a host of apparently unrelated problems, and for synthesizing the work of a great number of other philosophers. He developed an influential truth-conditional semantics, attacked the idea of mental events as governed by strict psychological laws, and rejected the conception of linguistic understanding as having to do with conventions or rules, concluding famously that "there is no such thing as a language, not if a language is anything like what many philosophers and linguists have supposed. There is therefore no such thing to be learned, mastered, or born with."codice_1 His philosophical work, as a whole, is said to be concerned with how human beings communicate and interact with one another.