Byars, an American artist who died in 1997, liked to include himself in his works, so asking questions seems the natural thing to do. It's a bit like peering at the detail in a painting to see if the brush work will tell you something more about the artist's method or the effect you get when you see it from a distance.

Luckily the interviewer in this 1969 film is not afraid to probe, and the results shed considerable light on the work of this enigmatic conceptual artist. It screens in the current show at Argos in Brussels with two other short films about Byars' work, from 1979 and 1995.

The 1969 film, made by Jef Cornelis for Belgian public broadcaster BRT, consists of conversations with Byars and images of his first solo exhibition on mainland Europe, at the Wide White Space Gallery in Antwerp. At this point, Byars was interested in plurality and structures that brought people together and blur their individuality. "If you are 75 people in one hat, are you one or 75?" he asks cryptically, before the image switches to show him installing slightly baffled Antwerpers into just such a group hat and having them walk through town. He even insists on conducting one conversation wearing a mask that links him to the interviewer.

Slightly more effective is the “Pink Silk Aeroplane for 100”, a vast piece of fabric with holes in to accommodate the heads of the “passengers”, who are told to sit underneath it with their knees drawn up, in rows of two. It's not clear whether they are there simply to be looked at, as part of what Byars calls a "soft sculpture", or part of the audience as well.

With his long hair, high-domed hat and star-spangled shirt, Byars comes over as wide-eyed visionary, with the same whimsical lilt and sense of wonder in his voice as David Byrne or Douglas Coupland. Listening to him fire off ideas is fascinating – and possibly more engaging than some of his work, which is more to the fore in the other two films. As with all performance art, you really have to be there.

The 100 Images are in One Second from 1979, also made in Antwerp, presents a rapid run through of his work, while Peter Brosens' The Death of James Lee Byars from 1995 shows the artist laying himself out in the window of the Marie Puck Broodthaers Gallery in Brussels, surrounded by gold leaf (pictured). It also explores a work of religious interrogation staged in Cologne called “The White Mass”.

Not in the exhibition, but available in the Argos library, is another Cornelis film on Byars called The World Question Centre. In this live BRT broadcast, Byars telephoned noted artists, scientists and media figures to ask them what question preoccupied them, and then discussed the answers with people in the studio.

This touches on a point that Byars makes in Cornelis' other film, that maybe it would be better to use public art funding to buy TV airtime rather than build museums, essentially establishing a museum on TV. Not for the first time he sounds as if he is way ahead of the internet. From now on, I will always think of Facebook as a whole lot of people sitting with their heads poking through the fabric of a big, pink, silk aeroplane.

Also currently showing at Argos are videos and photographs by Rinko Kawauchi, brightly documenting the minutiae of everyday life in Japan, and thought-provoking installations and videos by Austrian artist Ralo Mayer, inspired by the Biosphere 2 project. This utopian plan to create a sealed, selfsustaining ecosystem in the Arizona desert in the late 1980s failed when the human inhabitants fell out with each other and the oxygen began to run short.

Mayer probes the structures of Biosphere 2 and the blurring of research, science fiction and new age philosophy that discredited the project in the eyes of the media and the scientific establishment. He produces some intriguing ideas about ecology and how things might have been different if Biosphere 2 had taken place in the age of the internet, climate change awareness and reality television.

Until 27 March
Argos Centre for Art & Media
Werfstraat 13, Brussels
www.argosarts.org