Hidden Variables from 1989 is a 13-minute scherzo for a chamber orchestra of 15 players. It is a set of variations, albeit one that Matthews uses to explore, contrast and examine a host of musical styles – including his own – represented by composers like Terry Riley, John Adams, Phillip Glass, Louis Andriessen, and others. “Any resemblance to the music of living composers”, Matthews said of the piece, “is wholly intentional.” Matthews’ piece shows the breadth of his stylistic imagination and the many facets of his compositional language. Hidden Variables also exists in a version for full orchestra.