Early in the film Examined Life, literary theorist Avital Ronell asks the director Astra Taylor, "What are you getting me into here?" A pertinent question, because Taylor's new documentary makes for a grim outline: eight philosophers talking for 10 minutes each on anything from theories of justice to cosmopolitanism. The nearest we get to a car chase is a long, sweaty drive in an old Volvo to a lecture hall.

What it is, however, is an enjoyable experiment: moral philosophy – the motion picture. After all, your multiplex is more likely to show scenes of teenage devil worship than someone thinking. Film-makers have good reasons to avoid contemplation. For one thing, it is not a pretty business. As Oscar Wilde observed: "The moment one sits down to think, one becomes all nose, or all forehead, or something horrid."

That is less of a worry with Taylor's cast who, as American academics, are far better groomed than any troll to be found among the Bodleian library's stacks. But, more importantly, a medium of moving images will always struggle to depict thought, which often leaves film-makers inventing eureka moments. Think of that scene in Good Will Hunting where Matt Damon and his maths professor ecstatically scrawl on a blackboard.

Not only does Taylor avoid such hokiness, she also sidesteps the other elephant trap for documentaries of being too reverential towards their subjects. Each philosopher is presented without biography or bibliography, and filmed in transit – walking or rowing, and always, always talking.

The result is often exuberant. Slavoj Zizek – the world's first known cross between a Lacanian theorist and a grizzly bear – patrols a giant south London refuse centre and barks, "This is where we should start feeling at home," before blasting ecologists for their "conservative" notions of the environment.

As for the deconstructionist Ronell, she was right to be concerned. Teenagers who saw the crew filming in their park began chucking bottles. Yet the theorist was unruffled, reports Taylor: "She just said they reminded her of her students."