It is not easy to define the fundamentalist. Fundamentalism, for me at least, is an interesting phenomenon from the point of view of the theory of knowledge. What Protestant Christian fundamentalists seem to have in common is a literal interpretation of scripture, but this too may not be entirely accurate. Some fundamentalists hold that hermeneutics is very important, that is, careful interpretation that takes the language and historical context of scripture seriously. I often refer to "Catholic fundamentalists", but clearly and unambiguously articulating just what that means is not easy. I think I can safely say, however, that all fundamentalists are dogmatists.
Recently a friend of mine asked: "Should protestant fundamentalists be faulted for believing the plain language of the Bible rather than the more thoughtful and nuanced Catholic apologetics?" My best answer at this point is that I think people should be faulted for giving up their common sense and allowing their need for certainty to override it. Bertrand Russell once said that the demand for certainty is one which is natural to man, but is nevertheless an intellectual vice. He argued that "to teach how to live without certainty and yet without being paralysed by hesitation is perhaps the chief thing that philosophy, in our age, can do for those who study it".
The older I get and the more I observe, I find that Russell is right to observe that "The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts". Very few people today are comfortable with ambiguity, that is, with not-knowing. Many people suffer from a kind of "philosophical autism", a disordered need for closure, a need so great that discussion, debate, patient research, etc., is virtually shut down and opposing points of view are dismissed and ridiculed - people would rather have the illusions of knowledge because it brings them the desired security.
But the world is utterly rich in complexity, as a simple glance at the history of the developing taxonomy of physics or psychology makes manifest. In 1911, there were two branches of Astronomy: Astrophysics and Celestial Mechanics. Optics branched off into Theoretical Optics and Spectroscopy, and Acoustics was simply that, nothing more. But by 1970 there were 9 specialties of that branch of Astronomy called Solar-Planetary Relationships, 6 specialties of Planetology, and 11 further Astrophysical specialties, 9 specialties of Acoustics, and 10 specialties of Optics, etc. Consider how much psychology has developed over the past 200 years. There is only one human nature, but there are various schools of psychology: Structuralism, Functionalism, Behaviorism, Gestalt Psychology, Psychoanalysis (Freud), etc., and there are different perspectives, such as the evolutionary perspective, the biological perspective, the cognitive perspective, the humanistic perspective, the psychodynamic perspective, the sociocultural perspective, etc., and there seem to be far more branches of psychology now than there were when I first studied this back in the 80s: Clinical psychology, Counselling psychology, Educational psychology, Developmental psychology, Personality psychology, Social psychology, Environmental psychology, Experimental psychology, Industrial/organizational psychology, Cognitive psychology, Health psychology, Sport psychology, Forensic psychology, etc. In other words, reality is utterly rich in complexity and can be studied from various different angles and from innumerable starting points.
Moreover, knowledge is very hard to achieve, which makes life all the more interesting and exciting. Our own recent discussion of certain questions in the area of virtue ethics bore this out. You will notice that the more abstract and general the level of discussion, the greater the certainty, but as we descend to lower levels of abstraction (i.e., the realm of the particular and contingent), things become murkier and much more opaque. This does not mean there is no "truth" on this level; rather, it means that truth is much harder to uncover. General principles are always easier to handle than their application to particular situations, which is why mathematics enjoys greater certainty than say history. The lower the level of abstraction on which a science operates, the more inductive and conjectural is the method, and thus the greater the need for testing, which is why there are no labs in math class, but labs in chemistry and lots of sifting through archives in history. A similar pattern is noticeable in ethics. We all agree with the general principle that we ought to exercise reasonable stewardship of our excess riches (liberality), and we agree that people ought to dress modestly, that is, honestly and reasonably. But determining exactly where that line is and when it is crossed is not at all easy to determine. Some argue that tight jeans and yoga pants are immodest, while other students put forth very plausible arguments that such apparel is not at all immodest, but culturally normal and reasonable. Indeed, there are different cultural norms with regard to dress, and what is immodest here in Canada is not immodest in Africa. If wearing a bathing suit on a beach is reasonable, why is wearing yoga pants on a street only a half a mile from the beach unreasonable? When does fundraising in a school setting become excessive? Have we crossed that line at our school? Some put forth persuasive and plausible arguments that we have, while a few students have put forth an equally persuasive and plausible argument that we have not: i.e., one always has a choice to contribute, fundraising has an important educational value, while others point out that fundraising is outside the scope of the school's purpose, and students do not have an unlimited reservoir of coins that they can reach into whenever they are asked, which seems to be almost weekly, and unnecessary pressure is placed on students to donate, etc.
The beauty of the discussion is that it highlights the complexity and opacity involved in plausible reasoning. No one side was absolutely and unambiguously right, and no one was clearly wrong; every point made in class was a very insightful one that increased the plausibility of their side of the issue, and plausible claims just kept piling up. And in many ways, that was a better lesson than the simple deposit of "the right answer". I still don't know what the right answer is - regarding modesty and liberality - , although I lean less to one side than I did before we had the discussion. However, I know a young and rather smug seminarian who would put an immediate end to the discussion and declare, with great confidence, that the bikini is immodest. Done. No discussion. Clear and evident. Of course, it is far more complicated than that. Perhaps it was next to impossible to find a woman to model the bikini when it first came out - only strippers were willing. But that does not resolve the issue; in fact, it only begs the question; perhaps the social norm at the time was unreasonably prudish.
It's the complexity and resulting uncertainty that makes science very interesting as well. Reality is always much richer than we currently realize, which is why science continues to develop. Very few good scientists are "dogmatists"; they know that eggs placed in today's "scientific basket" will likely be overturned tomorrow, and thus they have a greater appreciation for the tentativeness of truth. Fundamentalists, of whatever stripe (i.e., Catholic, Protestant, Muslim, Hindu, Jewish, etc.), do not for a minute believe that truth is tentative. In their minds, it is absolute, clear, unchanging, etc. Indeed, in itself, truth is absolute and unchanging, but the "in itself" is an idealization. As Philosopher Nicholas Rescher points out: "Definitive truth is realizable only by way of idealization: actual inquiry presents us with estimates of truth, in matters of scientific theorizing, the real truth as such is realizable only under ideal conditions. We have no workable alternative to presuming that our science as it stands here and now does not present the real truth, but only estimates it. "Our truth" in matters of scientific theorizing is not - and presumably never actually will be - the final truth. However confidently science may affirm its conclusions, the realization must be maintained that its declarations are provisional, tentative - subject to revision and even to outright abandonment and replacement. But all this is not, of course, any reason to abandon the link to truth at the teleological level of aims, goals, and aspirations. The pursuit of scientific truth, like the pursuit of happiness, or for that matter any other ideal in life, is not vitiated by the consideration that its full realization is not a matter of the practicalities of this imperfect world" (Epistemology, 147-148).
All we have is truth "as I see it currently", as I have estimated and articulated it, as it appears to me within a limited model consisting of a number of epistemic conditions that were gradually acquired. If what I apprehend is true, then it will endure, it will never be falsified, but how do I know that further data - including rational data such as new insights spawned from new questions posed within different geographic and temporal circumstances - will not arrive on my doorstep next week that renders my current argument - made up of a large set of consistent propositions and premises - , inconsistent and far less plausible? It has happened countless times since I began to study philosophy; why would I assume that such a process would suddenly come to an end?
But dogmatists and fundamentalists find that realm of "unknowing" very uncomfortable. And the irony is that God is the unutterable mystery. The increasingly complex taxonomy of all the sciences is testimony to the inexhaustible richness, complexity, and depths of reality, and from a theological point of view, the latter is a sign of the inexhaustible and incomprehensible nature of God, the unutterable mystery who is the source of all that exists. God can never be comprehended (in the sense of fully understood or intellectually circumscribed). The evolution of the universe (13.6 billion years old), the evolution of the planet (4.6 billion years old), the evolution of life, the evolution of science, and the evolution of thought in general, should fill us with wonder, but instead some will rebel against it and demand certainty and stability. There's the congruity between science and religion: both center on mystery, and both require a similar attitude of "unknowing" and openness, an ability to live and breathe within a space of doubt.
My friend finished by asking: "How am I to recognize what is "simply a false or profoundly deficient" bit of inhumane ideology and what is the profoundly thoughtful, nuanced word of God?" That is a great question, and I wish I could answer it, but I can't, at least not at this point. It's like asking: How can I recognize what is good science from bad science, or fake news from real news, etc. I don't know. Discerning fake news from genuine news is about learning to be less gullible, learning to reason more critically, becoming very familiar with the fundamentals of logic, etc., but even that isn't enough. I don't think there is a way to discern what is genuine from what is not genuine from the sidelines, so to speak. In other words, there is no formula that one can isolate and use as a standard. One just has to get into the thick of things and deal with the messiness of reality and enjoy the adventure. There is no "paper" infallibility. Scriptural or sacred texts are read and interpreted by limited human beings whose minds are clouded by disordered passion. Although Catholics believe the bible to be the inspired word of God, there is a distinction between a proposition and an assertion, and yet determining what is asserted and what is not is no easy task. Biblical interpretation, like all textual interpretation, is an inductive process involving both deductive and inductive arguments. It is not and never has been a final and once and for all deal. There has been a development in the Church's understanding and interpretation of Scripture, and that understanding continues to develop in conjunction with new religious experiences, new advancements in science, psychology, and philosophy, among other things.