There are three levels of joint attention&colon; triadic, dyadic, and shared gaze. Some authors generalize from the term "dyadic" to related terms "triadic", "tetradic" and "polyadic". Beyond its application to triadic chord progressions, neo-Riemannian theory has inspired numerous subsequent investigations. This is called a "ternary or triadic relation" in logic. Another measure for the presence of triadic closure is transitivity, defined as formula 25. Consequently, pragmatic theories of truth are largely expressed in terms of triadic truth predicates. This was European classical music, based on parallel thirds and triadic harmonies. An increasingly refined cadence, and triadic harmony defined the musical work of this era. Meme is thus described in memetics as a sign without its triadic nature. The meme is thus described in memetics as a sign lacking a triadic nature. The triadic color scheme uses three colors equally spaced around the color wheel. It is an irreducible "triadic relation", according to Peirce. Peirce came to define representation and interpretation in terms of (triadic) determination. The primary colors are an example of a triadic color scheme. The triple-temple form of the triadic pyramid appears to be related to Maya mythology.