Many words have been written on the subject of symmetry in Bartók, prompted by the abundance and variety of examples of the phenomenon to be found on the music's ‘surface’. As yet, however, the fundamental stasis of symmetry and the dynamism for which Bartók's music is noted have not been adequately reconciled, irrespective of what kind of symmetry has been examined – spatial, formal, or pitch-class. One of the problems regarding work in the first of these categories has been that analysts have tended to examine excerpts rather than complete spans of music. Thus while Jonathan Bernard proposes that there is in Bartók a ‘hierarchy of relationships in which smaller symmetries contribute to larger ones, which in turn contribute to even larger ones, and so on, across ever larger spans of time’ – a theory which has the potential, at least, to account for dynamic aspects of the music – his concern only with incomplete spans limits the effectiveness of his approach.