The thesis 'Human Potentiality in the Early Writings of Karl Marx' considers the notion of human potentiality as employed in Marx's early texts and in those of his humanist followers. A distinction is made between an Open Humanism and a Closed Humanism. A Closed Humanism, in gesturing towards a Communist future, makes illegitimate use of the notion 'human potential', such that it assumes too easily that men, in fact, possess large amounts of unrealised potential and also makes unwarranted value judgements as to how it may be best realised. An Open Humanism, on the other hand, is proposed as a philosophically tenable means of referring to and justifying a Communist future. Rather than sketching the human content of the future, it maintains that, in the free conditions of Communism, men would be subject to the demands of a problematic of the good life. This problematic, is a reworking of a traditional philosophical question, most commonly associated with Aristotle, of how potentialities which are common and peculiar to human beings are related to the question of how they ought to live.