Yet it is not a medical textbook for which one requires specialist knowledge. It is a logical book of knowledge of that which we call "life". – Therefore this book is not a single-track textbook.
This book is a book for life

Yet it is not a self-help book along the lines of: "Do this and you will live happily ever after." Instead, it is an extremely honest book, one which offers the unvarnished truth on many important aspects of life, and offers real help for leading a sensible life.