Lucretius was the first writer known to introduce Roman readers to Epicurean philosophy. De Rerum Natura, written in some 7,400 dactylic hexameters, is divided into six untitled books, and explores Epicurean physics through richly poetic language and metaphors. Lucretius presents the principles of atomism, the nature of the mind and soul, explanations of sensation and thought, the development of the world and its phenomena, and explains a variety of celestial and terrestrial phenomena.