Another book on a subject that escapes myself I say .... well we took to me though this act of achat..le book is a compendium of research referenced informations..des accompanying the Analysis of the author at the same time that it seeks to awaken our; all in a clear style lamp - - (not bad for a commercial) audible in all cases and that helps one who has not had access to all this information from our elders on the subject; This is an important book offered by a rational dynamic author but very open with an analytical fineness which binds me to his reasoning.