Half a millennium after the event, the Renaissance still provokes debate. Was it a decisive break with the Middle Ages? Was its most important feature a new "way of seeing", a realist impulse in art? How did the Reformation factor into the Renaissance, and vice versa? And a dozen other A-level history exam questions besides.
The difficulty of pinning down such a complex, multifaceted concept seems worth thinking about in the context of whether we are living through a cycling renaissance. Wherever you look, there seems to be a new flowering of bike culture. This week, the Bicycle Film Festival returns to London. From its genesis in festival director Brendt Barbur's brain, after he was knocked off his bike by a New York bus, the festival has become a peripatetic global phenomenon. Highlights this year are a feature about the origins of mountain biking in 1970s California, Klunkerz, and more shorts from gonzo helmet-cam-wearer Lucas Brunelle.
Earlier this year, audiences in Brighton and London were treated to performances of "bicycle ballet" - a revival of an idea with a venerable modernist heritage, pioneered by Sergei Diaghilev's Ballets Russes. And there have been numerous exhibitions of cycling photography: the Getty archive gave some stunning images of past decades of the Tour de France an airing during the summer. The Host gallery in London has followed an exhibition about cycling in Belgium, Flandrien, with a 2007 selection of the best photography from the quarterly cycling glossy, Rouleur. And those who attended the Mildenhall cycle rally in Suffolk in August were treated to a show called Velorotic, chiefly comprising naughty French postcards dating back to the 1890s of women on bikes in combinations of hats, corsets, stockings, nice smiles and not much else.
This, and a hundred other instances I could mention, all feel like a reanimation of "bicycle culture". But what does that phrase mean, beyond being a capacious saddlebag in which to collect any art object whose content or theme is bicycle-related? For we also talk about, say, the "cycling culture" of the Netherlands, referring to something quite different - about how the custom of riding a bike is embedded in the warp and weft of everyday life. This is what transport planners are butting up against more and more: you can build all the bike lanes you like, but if people stubbornly stick to driving, how do you whistle up a cycling culture where there is none?
In which case, how do we turn the renaissance of bicycle culture into a reborn cycling culture? A question in which we all have a more than merely academic interest.
Matt Seaton's Two Wheels is published by Guardian Books at £8.99. Call 0870 836 0749 or visit guardianbooks.co.uk