Prom 20, Royal Albert Hall, London/ BBC Radio 3

Tavener-land revisited

Though not the same thing, reason and knowledge are related, and so the pairing of Sir John Tavener's Song of the Cosmos, concerned to highlight the limit of our reason, and Holst's Planets, whose subject relates to the changing extent of our knowledge of the universe, was a challenging one on the part of the Proms' director. Whether he had in mind the recent debate about Pluto's status as planet or asteroid is unclear, but the question of categories was relevant, too. For what answers to Tavener's view of the facts, whether those of the Fall and Resurrection, as preached in his millennial can-tata of that name, or the heavenly plan, as expounded in Sat- urday's premiere of Song of the Cosmos, is certainly debatable – no less so than the "facts" of astrology that inspired Holst in his famous suite.

Undeniable, however, is that music is only the sum of what we hear in it, making it good to revisit Tavener-land, where, for those who like that kind of thing, the world, like a monastery garden, is charged with the sound of ethereal voices. In Song of the Cosmos, as in one of Erik Satie's Gymnopédies, there's a sense you've heard it all before: the composer's favourite soprano, Patricia Rozario, sings ravishing melismata (in this case, as Sofia, from the lofty Albert Hall gallery), between massive chor-al statements, interleaved with a rumbling priestly bass (the impressively bearded if vocally reticent Deacon Meliton).

Then, having gone through these elements several times, the music comes to a stop, the period for Song of the Cosmos being a crashing entry of organ after a long crescendo, to show the end-point of our reason.

Modest in length by the composer's own standards, Song of the Cosmos none the less introduced a new, ecumenical spirit, in the form of the pulsing rhythm of classical Indian matras. With soprano, choir and bass symbolising, at their different levels, the Godhead, angels, Earth and mercy respectively, it was also a reminder that there's nothing quite like a Tavener premiere. Who else could get away with the luxury of slowly moving common chords belted out by the 200-odd voices of the Bach Choir for minutes at a time?

They were there, along with a capacity audience, to cel-ebrate the choir's 125th anniversary, for which the piece was commissioned. Were we also witnessing another new stage in the composer's development, now extending to embrace both Orthodox and Indian elements in further summative statements?

Conducting The Planets without a score, Yan Pascal Tortelier drew soothing solos from the BBC Philharmonic in "Venus", after a gripping "Mars" that made war sound thrilling. "Uranus" was played without the camp swagger that so often disfigures it, while the opening of "Saturn", the Bringer of Old Age, was revealed in this fine performance as what it surely represents: the impassive ticking of an ancient grandfather clock.

This Prom will be repeated tomorrow at 2pm on Radio 3