Rock and roll is turning 60 about now. The exact date depends on who is reminiscing. But should this event be treated as a birthday celebration or a memorial?
In music, the most basic genre distinctions - classical, jazz, rock - stagger on in the 21st century, despite the efforts of many to render them defunct.
Accounts of rock's demise have been protracted and painful to observe. Yet rock has been defined in so many different ways that the very idea of a definitive start (or end) seems suspect.
Most orthodox interpretations of the genre betray a kind of bell-curve existence. Here the story begins in the mid-1950s, peaks with the Beatles, then undergoes a long descent through punk and beyond.
Nothing reinforces the waning of rock music more than the rock canon. Every aesthetic form develops narratives of consecration; no other has seen consecration taken to such repetitive extremes.
For decades, listeners have compiled countless lists of rock's greatest albums in barely altered arrangements.
The Beatles are immovable at the apex of rock and roll glory, something many music scholars agree with audiences on. The sheer volume of Beatles-related reference texts is astonishing.
Recent debates among nostalgia buffs centre on whether the Beatles' Revolver album has overtaken Sgt. Pepper's Lonely Hearts Club Band, long considered the genre's foremost artefact.
For their 2013 book 100 Best Albums of All Time, Australian authors Toby Creswell and Craig Mathieson claim a subversive coup by rejecting the latter in favour of its predecessor.
Yet what the Beatles also evoke is rock's disintegration as a clear-cut style.
Reductive takes on their legacy contrast with the innovative nature of their music. The 1967 cover of Sgt. Pepper's gives a clue here. Peering out morosely from the back row of that celebrity gathering is German composer Karlheinz Stockhausen, whose pioneering Hymnen (Anthems) appeared the same year. Hymnen suggests contradictions and cross-fertilisations; it speaks of sonic borders being torn down. The next year, the Beatles were channelling Stockhausen with Revolution 9 from their White Album.
At the time Paul McCartney expressed admiration for Stockhausen and fellow modern composer Luciano Berio, saying he was "sick of doing sounds that people can claim to have heard before".
The Beatles were always looking ahead, so it is ironic that their high points are now frozen in time as insurmountable monuments.
Unfortunately, the subsequent rock canon incorporates diversity only in perverse ways. Inventive new artists are shunted out to the margins, ushered there by ageing baby-boomers who long ago pronounced the landscape of rock music to be "thoroughly explored".
Rock has now devolved into what British writer Simon Reynolds terms "a delta of microcultures", each fragmenting at frightening speed - from metal to rap to alt-country, from drone to dubstep.
While there is much fine rock-inflected music being made today, the contradiction remains that deeply nostalgic celebrations of rock only serve to strangle it as a living form.
As long as the acclaim is mostly for what was, not what might come next, the extended death throes of rock will likely continue to play out well past its 60th anniversary.
James Jardine has a PhD in cultural studies and is a tutor at Griffith University in Queensland.