Artha-shastra is about generating food, i.e. wealth, by creating goods and services; Kama-shastra is about indulging our hungers with this food. Dharma-shastra insists we consider the hunger of others, while Moksha-shastra is about outgrowing our hungers, in order to be detached and generous. Together, these four Hindu shastras provide a framework within which human action, its purposes and consequences, can be defined; together, they validate human existence and give it meaning.
In Dharma Artha Kama Moksha, Devdutt Pattanaik uses his unique understanding of mythology to provide an accessible and lucid guide to the Hindu way of thinking, with short essays that are crisp expositions of important concepts.