In Momentum the fallibility of human aspiration and the comparatively certainty of concrete, are both seen to be parts of a constantly changing river of colour and light. The monumental solidity of the concrete ruins are thus seen to be as unstable and as tenuous as both the lives of those who built them or those who have since inscribed their identity on the crumbling walls.Although we may find consolation in the idea that the world around us is predominantly stable with only an occasional disruption to the fabric of our personal realities, it is probably more realistic to understand, as Heraclitus did more than a thousand years ago, that pockets of stability are in fact, unusual and temporary and that the only constant is continuous change.