What does lightness have to do with trams in Calcutta and Melbourne? A lot, according to Australian artist and designer Michael Douglas, who is also Program Director of RMIT University, Melbourne. Like electronic technology, tramways are characterised by their non-linear operative logic of movement. Douglas believes a dialogue with tramways can mobilise possibilities of lightness for the urban condition. At Doors 6, he will propose ways of thinking about tramways and the city, as well as describing aspects of the art-activism project Tramjatra, which is about "imagining the cities of Calcutta and Melbourne by tram." Over the last three years, Tramjatra has been creating temporary public artworks which illuminate the culturally enriching and environmentally sustaining potential of tramways. Tracks enable movement, points our Douglas, yet prompt us to review the way we move. Tracks allow repetition; yet, as Derrida stated, "Repeated, the same line is no longer the same." The tramline, like the design process, is a continuous movement, a journey with no pre-ordained conclusion and no fixed destination. In a purely practical sense, trams are a form of urban transport that embodies lightness, or sustainability. On a more symbolic level, tramlines also offer ways of understanding and interpreting less concrete 'movements' such as information systems and thought processes. Douglas has collaborated with Karachi University, Pakistan, and the National Institute of Design, India. His public artworks have appeared in places as diverse as Melbourne Cricket Ground and on public television; they include a life-size caravan made of birdseed, which was eaten away by pigeons.