Watch full movie online. "Of the new foreign work I saw, (at the Avantgarde Film Festival in London) that of Taka Iimura interested me most – His film + & -, using scratched signs, displayed how perception can be molded by the concept. By postulating negative duration – a length of black, say six seconds, minus a length of white, say three seconds, equals a length of black three seconds – the gradually emerging experience of 'backward running duration, through a long series of these visual sums, was very surprising." Malcolm Le Grice, Studio International, Nov. 1973