Two major notions dominate this book:
1) meaning systems
2) the principle of intratextuality
The idea of meaning systems seems to add practically nothing to the lay understanding of "meaning", as when I might say "This gives meaning to my life". If I were to ask myself just how it gave meaning to my life, I might note some behavior or behaviors of mine that indicated the meaning. Lay people like you and I can do this: psychologists add little if anything by elaborating on such understandings via the notion of "meaning systems". If someone comes to your door holding a Bible and wanting to share with you their feelings of being saved, you can assume without resort to psychologists that your visitor feels they have found something meaningful.
The principle of intratextuality is a fancy term. The authors "assume that fundamentialists are correct when they argue that a reader must go into the text and allow the text to speak for itself". They take this remarkable assumption very seriously, adding that "no discussion of fundamentalism can proceed meaningfully if it refuses to enter into the text and be obedient to the imperatives of the text". Covering Christian and Islamic fundamentalism, it seems amazing that the authors were able to be "obedient to the imperatives" of both the Bible and the Koran. Did some of the authors refuse to obey the imperatives of one text while the other authors refused to obey the imperatives of the other. Or did they find a way to obey both simultaneously. Or did they obey one, then renounce it so they could obey the other? Do they assume any imperatives of science that they remained obedient to during this process?
What you won't find in this book are interviews with fundamentalists or survey results gathered from fundamentalists. What you'll find here are speculation (some of it identified as "model-building") and assertion. The authors deliberately do not try to explain how a person becomes a fundamentalist: they assume that one has and then "describe" the effects. They don't offer any methodology for this describing, although description can be quite selective and, hence, biased. They don't describe problems fundamentalists have maintaining their faith. They don't describe people who leave fundamentalism; they don't describe people who go to Fundamentalists Anonymous. With some much emphasis given to the sacred text as "speaking", the role of leaders, the impacts of conformity or collusion, and consideration of possible manipulation go unaddressed. At times, it is not clear from the voice of this book whether the authors are speaking or whether they are describing what they think fundamentalists would say, as on page 36: "The text does not contradict itself". Perhaps this is the voice of a fundamentalist but, the authors having opened the book with an "About the Authors" that associates them with fundamentalist backgrounds and sympathies, it's hard to tell. For one of the authors, Ralph Hood, it states in this opening "About the Authors" section that he believes fundamentalist religion has been poorly portrayed in the psychology of religion ... " and the book's concluding paragraph states "Our purpose in this book has not been to defend fundamentalism as much as to critique the efforts of some scholars outside fundamentalism who are quick to assume nothing good can come of it". So is this book research or polemic? Is it held that if one picks any book as sacred and follows its dictates, that some good will come of it? Or does this just apply to the Bible and the Quran? If so, why? Perhaps the advice is to wait and see if some good comes of it and then sanction that book. Must just some good come of it or must it be on balance good. Who judges and how that when one picks up snakes enough good comes of it? If the authors can determine whether some good comes of fundamentalism, presumably they can determine whether more good comes of Christian fundamentalism or Islamic fundamentalism.
If we want to understand fundamentalists, perhaps we should just speak more with our fundamentalist neighbors, co-workers, and friends. And be skeptical of experts.