Like all informal logical fallacies, the argument from authority is often less a cheap rhetorical tactic than a misemployed heuristic. Because (by definition) a significant burden of evidence or reasoning has been shifted to an authority, whatever scrutiny might have been aimed at that evidence or reasoning now bears upon the source of authority.
In fact, authority is, at least in today’s world, an indispensable source of belief. For instance, when getting dressed we implicitly rely on several authorities: To believe that our clothing is appropriate for the day’s weather, we rely on the authority of weather forecasters; that it is appropriate for our occupation, that of tradition or of seniority; that it is appropriate to our appearance, that of fashion; that it has not been negligently laced with toxins, those of moral standards and of government regulatory agencies; and so on.
Obviously there are authorities generally, or at least widely, thought to be reliable that nonetheless are not. We can know this not just because authorities disagree, but because we have more reliable sources of evidence regarding many things in life than authorities. For example, we don’t (or oughtn’t) rely on weather forecasters to know whether it is currently raining in our own neighborhood, or on political commentators to know whether wealth is fairly distributed, or (solely) on the generic advice of any of our confidants to know what course of action to take with respect to a thorny social situation.
An especially common authority cited with regard to an issue is the expert—someone trained, knowledgeable, and experienced in the issue itself or in some discipline(s) relevant thereto, who can convey and contextualize current best knowledge on the subject and its implications for people’s lives. We rely on the experts who prescribe our meds and tune up our bikes as much as we rely on those who inform our healthcare professionals and policymakers. When an expert speaks about their area of expertise, we tend to listen. (While it’s another story in itself, we even tend to listen carefully to experts when we’re predisposed to—even intent upon—doubting them. When we fall into denial, we crave their validation even as we reject their credibility.)
A while back a muslim redditor asked a novel question, which i suspect lies toward the heart of many people’s attachment to religion in a (comparably) secular society, especially as a source and framework for morality:
So a lot my atheist friends tell me that I am “nitpicking” the good parts of Islam and the Quran and ignoring all the bad stuff that it preaches. I completely agree with them, I do that all the time. Ive just wondered why that is considered bad. I understand that if I dont follow all of the rules, Im not really 100% muslim, but thats okay with me. Im only like 75% muslim. I only believe in the part of the religion that I want to, but I think I believe in enough to still call myself a follower. Is that wrong?
This gave me the chance to expound upon a perspective on scriptural morality i’d been nursing for some time, and my response was well-enough liked that i suppose it’s worth expanding upon here.