The title refers to an element in an equation that remains the same regardless of the shifting variables around it. For Witold that is the corruption of the world around him. When his mother is hospitalised, his upstanding demeanour and condemnation of her doctor - who is on the make - guarantees that she is left in a drafty corridor rather than given a more comfortable room. At work, he refuses to condone colleagues skimming off expense accounts and even raises the matter with unmoved superiors. Witold could turn a blind eye, protecting his own conscience but submitting to societal pressure, but when he won't life becomes problematic quickly. "You have to accept the world as it is," a friend tells him. "That's maturity." Maturity may, in fact, be something Witold is in pursuit of. Since childhood he has harboured the dream of going on a climbing expedition in the Himalayas - where his father fell to his death when Witold was but a boy.
Obstacles are perennially placed in the path of this goal and it is, perhaps, the act that would ignite his realisation. Slawomir Idziak's visuals evoke the snowy cold with a chilly aesthetic and a camera is a little more restful that in some other of Zanussi's films from this period. Alive when it's rattling down a ski slope in the directors inimitable style, Idziak also manages to pick out the hidden geometry of scenes before intimately following Witold's journey. Mathematics and raw intelligence are sidelined a little more than in some other works, but this is still another scientifically astute Zanussi lead, whose naivety proves as touching as it is debilitating. With faith, guilt, love, greed and sacrifice all woven throughout, The Constant Factor may not be the most flashy in Zanussi's catalogue, but it's still a hell of a show.
The 13th Kinoteka runs from 8 April - 29 May. The full 2015 programme, ticketing details and more can be viewed at kinoteka.org.uk. You can follow our coverage here.
Ben Nicholson | @BRNicholson