But for most of its early critics the Eroica was a puzzle. Few of them denied the power of Beethoven's imagination, but equally few of them seem to have been able to make sense of it - and the same was surely true of the performers. Critics of today's new music should be made to read some of those early reviews. It is - or ought to be - a humbling experience. How can we hope to do any better in the face of the truly new, truly original products of our own time?
It is quite possible that one day there will be a performance of Hans Werner Henze's new Eighth Symphony that silences all my doubts - a performance as deeply, thoroughly understanding as was Sir Simon Rattle's account of the Eroica in the second half of last Friday's Prom. The chance to hear it again would be very welcome, if only to re-savour the sounds Henze creates. There are passages in some of Henze's works that are like the opening of a door on to another world - a luxuriant, magical world.
The Eighth Symphony has plenty of these; well, what else would you expect in a work inspired by Shakespeare's A Midsummer Night's Dream? Images from the play come flying by in droves. In the outer movements you can virtually see the banks blowing with wild thyme, "quite over-canopied with luscious woodbine". The robust Stravinskian dance, with pounding drums and strutting bass brass, that ends the second movement just has to be a triumphant procession for rude mechanicals.
But, as so often with Henze, the thread that holds the sea of images together - Puck's "girdle round about the world", if you like - is hard to find. The problem seems to lie in the linear dimension. Phrases start magnificently, with big intakes of breath - surely a marvellous singing melody is going to unfold. But more often than not the line peters out just when it seems to be gathering strength. Maybe there is a larger, hidden line that binds all these so promising fragments together - just as there is in the seemingly fragmentary textures of the Eroica. If so, Rattle and the City of Birmingham Symphony Orchestra didn't find it.
Still, the memory of those gorgeous sounds won't go away; the lure of Henze's sound-world is still powerful. We need to hear the Eighth Symphony again. Until then, there will be the memory of Rattle's Eroica. Here was a performance that seemed to have taken inspiration from many different sources: from Nikolaus Harnoncourt and the period instrumentalists on the one hand; from past masters like Toscanini or Klemperer on the other - and was there a hint of Furtwangler in the allargando at the first movement's grindingly dissonant climax? And yet nothing sounded second-hand. The absorption in Beethoven's symphonic idea, from grand design to tiniest detail, was exceptional. We may think we know the Eroica well enough, but performances such as this show us how much we still have to learn.
n Tonight's Proms: BBC Scottish SO / Brabbins 7pm; BBC SO / Knussen 10pm. Royal Albert Hall (0171-589 8212) and BBC Radio 3Reuse content