18. PREFACE - Our bad instincts result from the imperfections of our own Spirit, and not from our physical body. If this were not so then Man would be exempt from all responsibility. Our betterment depends on ourselves, because every person who has all their faculties has in everything the liberty to do or not to do. In order to do good the only thing lacking is will-power (See chapter 15, item 10 and chapter 19, item 12).