Body language that exist in all languages. Body language, on the other hand, does not have a grammar system and must be interpreted broadly, instead of having an absolute meaning corresponding with a certain movement, so it is not a language like sign language, and is simply termed as a "language" due to popular culture. In a community, there are agreed-upon interpretations of particular behavior. Interpretations may vary from country to country, or culture to culture. On this note, there is controversy on whether body language is universal. Body language, a subset of nonverbal communication, complements verbal communication in social interaction. In
Pre-established harmony Pre-established harmony Gottfried Leibniz's theory of pre-established harmony () is a philosophical theory about causation under which every "substance" affects only itself, but all the substances (both bodies and minds) in the world nevertheless seem to causally interact with each other because they have been programmed by God in advance to "harmonize" with each other. Leibniz's term for these substances was "monads" which he described in a popular work ("Monadology" §7) as "windowless". Leibniz's theory is best known as a solution to the mind–body problem of how mind can interact with the body. Leibniz rejected the idea of physical bodies