Existentialism is a cultural and philosophical movement which is most associated with a European tradition in the middle of the twentieth century. Although it extends much further (into Japan, for instance), it is on this western philosophical tradition that Essays on Existentialism focusses. Likewise, it is only the classical French existentialists Jean-Paul Sartre and Albert Camus, and the earlier founders of existentialism, Friedrich Nietzsche, Søren Kierkegaard and Fyodor Dostoyevsky, that are the objects of scrutiny in Essays on Existentialism.
The first two essays constitute notes on Nietzsche's Eternal Recurrence. The first rejects the contemporary claim that Eternal Recurrence overcomes the 'problem of nihilism', the second that there can be no counterexample to demonstrate its falsity insofar as it is not a theory that can be falsified as such. The third essay addresses the Absurd in Camus' Myth of Sisyphus - specifically the myth itself. The myth of Sisyphus is properly metaphorical of how daily existence is. Life is Absurd: it must continue, can never cease for a moment - 'time waits for no man' - but it never means anything.
The fourth essay is a discussion and vindication of Sartre's conception of radical freedom. The existentialist doctrine of the will has been criticized plenty. However, existentialism is easily defended from these kinds of common criticisms: most stem from misunderstanding the doctrine.
The three essays following broadly concern existentialist ethics. The topic of the first is Iris Murdoch's criticism of existentialism vis-à-vis its system of ethics. The second concerns ethical egoism. And the third is an application of existentialist ethics to the sophist Gorgias' Encomium of Helen.
Included is an appendix on what it means to be young in an ageing world. The leading concept in the discussion is a novel theory of the gravity of choices.