This engaging book certainly lives up to its title, being small enough to fit into a jacket pocket and slim enough not to weigh you down. Sellars goes through those areas of Epicureanism most appropriate for a modern non-specialist audience and interprets the ancient wisdom through the eyes of modern life. Epicureanism was misrepresented and misunderstood even in antiquity, and this little book is a worthwhile corrective to the false notions which continue to attach to the word ‘Epicurean’.

After an opening chapter on the therapeutic value of philosophy – an important aspect of many ancient philosophers – Sellars homes in on the ‘path to tranquillity’ by means of the Epicurean mantra of the ‘little which is enough’. Epicurus argued that wealth and poverty are relative concepts and contentment is better achieved by limiting desires than by heaping up worrying amounts of wealth. Pleasure was seen as the greatest good, but Sellars is right to show that this is no hedonistic free-for-all since pleasure consists largely in the relief of pain and overindulgence will cause pain and so be counter-productive. Friendship as a key ethical desideratum is given a chapter to itself – although Sellars curiously says nothing about Epicurus’ wary attitude towards sexual relations in general and romantic love in particular, and sexuality is also conspicuous by its absence in the discussion of the different types of pleasure.

Chapter 5 (‘Why study nature?’) explains the atomic theory and stresses its value for the anti-teleological world-view which removed divine agency from the creation and maintenance of the world. Sellars stresses (correctly) that Epicurus was no atheist but rather viewed the gods as paradigmatic of our own potential for tranquillity: there is nothing to stop us from ‘living a life worthy of the gods’ as Lucretius tells us (3.322). Sellars might have added here that the study of nature is itself a source of pleasure (cf. Lucretius 3.29-31) and thus is desirable in itself.

Chapter 6 (‘Don't fear death’) examines the biggest enemy of human happiness and shows how (for the Epicurean) death, as the end of all sensation, is neither good nor bad as it produces neither pleasure nor pain. Furthermore, we did not mind being dead before we were born: as the man once said, the living are just the dead on holiday. Sellars poses some excellent critique of this simplistic view, showing how we might reasonably be unhappy at the thought of potential years of life being taken from us – a point picked up in antiquity from Philodemus onwards. The only answer for the Epicurean is to live in the moment and carpe diem.

Chapter 7 (‘Explaining everything’) is mostly devoted to the Roman poet Lucretius. Sellars briefly revisits the atomic theory and shows how it underpins every aspect of his observations of the universe and of our own experiences of it. Even when the poet is wrong he is always working from consistent principles concerning the nature of matter and void. Lucretius (5.564-5) famously claimed (p. 107) ‘that the sun is only about as large as it appears to us’ but he was by no means alone in saying this – Heraclitus thought the sun was the size of the human foot – and he had already argued hard (4.216-822) for the veracity of sense-perception in the face of Sceptical opposition. Epicurus himself (Diogenes Laertius 10.91) is somewhat unclear on the subject and mathematical astronomers in antiquity produced speculations that the sun was in fact 18 times the size of the earth. Nobody actually knew who (if anybody) was right. At this point it would have been helpful to the reader for Sellars to explain the Epicurean account of perception as simulacra emanating from the atomic surface of objects to illustrate the wider epistemological difficulties of which celestial objects are just a part.

Sellars does not always spell out the logical basis behind the arguments. Early mankind, for example, must have developed social bonds as (if they had not done so) the race would have died out and we would not be here (p.108). This is classic modus tollens: (If P, then Q: but not-Q: therefore not-P) and helps to explain how the poet managed to produce intelligent hypotheses about things he had not seen, ranging from the world of the unseen atoms to the furthest reaches of the cosmos. The history of the growth of human civilisation is fascinating – not least because it is the polar opposite of the ‘golden age’ notion found in poets such as Hesiod – and Sellars well points out that it serves the Epicurean materialistic view which excludes divine agency and which finds naturalistic explanations for everything, as well as helping us to see how we can live in accordance with our nature: ‘this poem combining cosmology and anthropology is fundamentally offering lessons in how to live’ (p. 111).

Sellars inevitably simplifies his material for a non-specialist readership and sometimes raises a reviewer's eyebrow. He assumes (for example) that Horace is a mouthpiece for Epicureanism even though Horace explicitly said (Epistles 1.1.14) that he belonged to no one school. A book of this size inevitably cuts corners and it is to be hoped that readers will pursue the recommended further reading to investigate the finer details. That said, this little book punches far above its modest weight and is a lively and energetic account of Epicureanism, ideal to be put into the hands of anyone of any age who wishes to know just why Epicureans were not epicures and how they managed – armed with nothing more than their senses and their brains – to shape the future of physics for millennia and to inspire a whole counter-culture of what constitutes the ‘good life’.