Die deutsche Ideologie
Some needs are far more important than others. In "The German Ideology" Marx writes that 'life involves before everything else eating and drinking, a habitation, clothing and many other things'. All those other aspects of human nature which he discusses (such as 'self-activity') are therefore subordinate to the priority given to these. Marx makes explicit his view that humans develop new needs to replace old: 'the satisfaction of the first need (the action of satisfying, and the instrument of satisfaction which has been acquired) leads to new needs'.