Zeno's extraordinary and disturbing paradoxes, the atomic theories of Democritus that so strikingly anticipate contemporary physics, the enigmatic and haunting epigrams of Heraclitus - these are just some of the riches to be found in this collection of writings of the early Greek philosophers. Jonathan Barnes's masterly Introduction shows how the most skilled detective work is often needed to reconstruct the ideas of these thinkers from the surviving fragments of their work. But the effort is always worth while. In forging the first truly scientific vocabulary and offering rational arguments for their views, the pre-Socratics were doing something new and profoundly important; they also posed the questions that have remained at the centre of philosophy to this day.