This book goes far beyond the issue vegetarian / non vegetarian, as it is also written in 4th cover: "Whether you are vegetarian, vegan or inveterate meat eaters, you will take advantage of all painful errors the author and his sharp eye to a healthy diet and all that that entails. " After reading it, it is so true. This book is really for everyone, if one has at heart to live more in harmony with our planet, that is the question of vegetarianism or not. In summary, this book is really a humanist manifesto and love of nature and life, full of subtleties (out of a vision all black or all white), to legitimate questions ... but it is also a book very well documented with plethora of sources, studies of all kinds (historical, ecological, nutritional ...)