Tonality is a modality with some restrictions on possible groupings. The set of all groupings in a tonality is the harmonic variety . Every grouping has its specific properties depending on its position within the tonality. We call tonicity of the grouping the F-potential reduced by the entropy of the sounding. Harmonic functions are groupings from a harmonic variety with extreme properties.
Tonic function is the grouping with the maximum tonicity.
Dominant function is the grouping with the maximum positive continuity towards the tonic. Subdominant function is the grouping with the maximum negative continuity, i.e. the maximum positive continuity in the direction from the tonic. Phrygian function , is the grouping with the maximum impulse towards the tonic from above. All things we can derive from the vertical bindings are part of harmonic statics , all other things belong to harmonic dynamics . We inspect groupings isolated from any harmonic context in the harmonic statics.