Boulez’ Structures for two pianos was written in 1951, in the same year as Cage’s Music of Changes. The two composers had been in close written and personal contact, exchanging ideas on the technique and aesthetics of composition. The methods they used where different in major respects. Cage’s method, using the I Ching to choose from the materials that he had decided upon beforehand, has come to be regarded as an ‘experimentalist’ one: the outcome is not known in advance. Boulez has since become known as one of the founders of ‘integral serialism’ which instead offers a system of control where an ordered series (a series of proportions, relations, or numbers, preferably derived from the pitch series) should provide the starting point for moulding all aspects of music– pitch, rhythm, duration, register, harmony and sound/instrumentation (Boulez describes his method to Cage in their correspondence in Pierre Boulez, John Cage – Correspondances et documents, J.-J. Nattiez (ed.) Amadeus 1990).
However, the very idea of a ‘method’ (literally, a road that guides our footsteps to a certain result or endpoint) is central to the thinking of both – a distinctive trait of many ‘avant-gardists’ in the last century. (I should immediately make an exception for Edgard Varèse, who despised every kind of preconceived system, especially Schoenberg’s serialist dodecaphony.)
About ‘method’ I would like to make clear the following. In earlier music, say, Beethoven, we talk about ‘techniques’ such as counterpoint, motivic development, variation, and perhaps even about harmonic ‘technique’. We also talk about ‘forms’ like sonata and fugue. There is a plethora of books that study these techniques and forms, from which we may learn how to apply them. Yet, we do not speak of ‘method’ in the sense that we use the term with Cage or Boulez. Now you might ask, given such a body of ‘rules’, what is the difference between them and avant-gardist ‘methods’ except that the avant-gardists made their own rules? Now, if history shows anything it is that such central practices simply came before ‘theory’. The essentials of harmonic counterpoint, the recognition of the fundamental bass, the concept of the sonata form, even the description of free atonality all came roughly half a century or more after they first occurred in musical practice and these descriptions codified what had actually been going on in practice – only then to serve as ‘recipe books’ for later generations. It is in this last stage that the theory (reading about the rules) comes before the practice (the hearing and playing). Especially in the 19th century this attitude resulted from the idea that the textbooks actually gave to a kind of realistic, naturalistic description (‘theory’) of the very ‘laws’ of music – that could simply be put into practice again.
For Cage and Boulez, ‘method’ was not at all ‘theory’ in the 19th-century way, a ‘naturalistic’ description that might serve as a guideline. They deliberately sought a means to break away from the musical ideas and practices of the ‘Old World’ – meaning, for Cage, the American composer: Europe at large, and for Boulez, the European, having the extra meaning of breaking away from pre-World War II Europe.
As Cage says a propos the chance technique used in his Music of Changes:
‘It is thus possible to make a musical composition the continuity of which is free from individual taste and memory (psychology) and also of the literature and ‘traditions’ of the art.’ (in: Pierre Boulez, John Cage – Correspondances et documents, J.-J. Nattiez (ed.) Amadeus 1990, p. 172) Boulez is a sense much more traditionally a ‘composer’ when he says that: ‘One could conceive a musical structure in two ways: one by serial combination, where structures arise automatically from relations between numbers; the other, by [ …] combinations in which [the] choice [of the composer] plays a major role. Both ways clearly offer a dialectical means of musical variation that is very effective’ (my translation).’ (ibid., pp. 162-3)
It is this ‘dialectical means of musical variation’ which Boulez was to elaborate in a major work from the mid-fifties: Le Marteau sans