In the opening sequence of his 1968 film 2001 – a space odyssey, Stanley Kubrick offers a stunning image of the beginning of warfare when one of his ape men picks up a long bone from a decaying animal carcass and uses it to bludgeon an opponent to death. In Kubrick's brilliant orchestration of this moment there is a palpable sense of awe and wonder among the creatures as their minds come to terms with the magnitude of the discovery. To Kubrick, it is a defining moment – the beginning of man's progress to civilization. This is a stark, uncomfortable, message which we need to examine in some detail.

Enter the philosophers

The nature of human aggression has long fascinated philosophers. One of the first to confront the problem head on was the British philosopher Thomas Hobbes (1588–1679). Oxford-trained, he lived through, and survived, the Civil War, an experience which cannot have failed to have had an impact on his thinking. Politically he walked a difficult tight-rope. He was a firm believer in strong government, and therefore supported the King against Parliament, but he was not prepared to accept the divine right of kings. His basic philosophy was that of a materialist who believed that rational explanations could be found for all human behaviour.

In his famous work Leviathan, published in English in 1651, he addresses the question of ‘the state of nature’.