'A superb actor' - tenor Ian Bostridge
'A superb actor' - tenor Ian Bostridge

The Great War theme of the International Festival reached boiling point this week with two remarkable performances in the music programme. It's impossible, of course, to separate the memorial events from the current hotspots, and that strange and idisyncratic tenor Ian Bostridge made the most telling statement about the attacks on Gaza by not referring to them at all in his stunning Tuesday morning concert in the Queen's Hall.

Bostridge's programme of songs - accompanied on the piano by the exemplary Julius Drake— included tales of love and war, the beating drum and the dying soldiers, the nightmare and the slaughter, by Gustav Mahler, Kurt Weill and Benjamin Britten. He closed with Britten's setting of Scottish poet William Soutar's "Children":

"Silence is in the air: The stars move to their places... But from earth the children stare, with blind and fearful faces: And our charity is in the children's faces." Bostridge finished, staring himself into the silence of the concert hall. He wouldn't let us go. We couldn't applaud. For at least 30 seconds. Then we applauded. There was no encore. How could there be?

Bostridge is the opposite of a heroic tenor and even in his sunniest moods - which are rare, and non-existent this week - he doesn't "give out" to the audience. But he is a superb actor, and his elegantly contorted frame and agonised facial expressions conveyed every twist and bitter turn of these war-torn musical vignettes.

Like everyone else earlier this week I was still reeling anyway from the Russian dramatic tone poem The War on the International Festival. Then on Monday afternoon, another unforgettable experience: Messaien's Quartet for the End of Time, composed when he was a prisoner of war at the Nazis' Stalag VIII-A camp in Silesia, performed in the stark beauty, lit by stained glass windows, of Greyfriars Kirk. The piece was premiered in the camp in 1941 to an audience of 400 fellow prisoners and Nazi guards.

"The most heartfelt and cathartic applause I've heard all festival"

How music of such transcendent beauty can both express human tragedy while touching on the sublime is one of the mysteries of great art, something to do with the spirit of endurance and faith in the afterlife (Messaien was a devout Catholic) or at least in the ineffability of love. Listening to the quartet of clarinet, violin, cello and Scottish pianist Steven Osborne on piano, was nothing short of shattering. And of course only work of this artistry and intensity can fully express the eternal truth about war: nobody wins, and nothing redeems those who perpetrate atrocity, wherever and whenever. As with Bostridge, the audience was stunned into silence. There was applause, eventually, the most heartfelt and cathartic applause I've heard all festival.

Sublimity sits well in Edinburgh. Standing at the top of the Mound, at the entrance to the Assembly Hall, you can see right out to the Firth of Forth over the rooftops of the classical New Town. These views never cease to delight and distract, and they always take me back to the first time I brought my young son (then aged nine) to Auld Reekie. As we crossed North Bridge with the castle away to the right, the crags of Arthur's Seat away to the left, he simply asked me if there was any other city like Edinburgh in Britain. He answered the question himself by spending the next few days walking round it with me.

Although the International Festival has reported record ticket sales, the Fringe seems a lot quieter this year. The Pleasance Courtyard doesn't seem as packed as usual, the area of the Usher Hall, Traverse and Royal Lyceum is almost eerily quiet by day-time, and the Film House a no-go area (it used to be so buzzy at festival time; the film festival now happens earlier in the summer). Mind you, when the sun comes out, everyone cheers up a bit. But I have one modest suggestion for the International Festival: how about some big splashy flower displays in the Usher Hall and, more especially, the Queen's Hall? I know this is the city of John Knox, and that we're remembering the Great War. But the austerity of these great venues would be enhanced if thrown into relief by some floral decoration.

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