Experts know more about their subject of expertise than you do. So, if you discover that you possess a view that contradicts the vast majority of experts, it’s more likely than not that they’re right and you’re wrong. In determining your own level of confidence on a matter, this is an important fact to keep on the table (and not brush it under a rug). Finding out the opinions of experts on a matter is not meant to arrest your own process of critical evaluation, or default that process over to others, but weighing the opinions of experts is part of critical thinking. Below are four suggestions for doing this sensibly:
- On the matter that concerns you, discover whether expert opinion has (a) arrived at a broad consensus; or (b) is divided. For example, with regard to the age of the earth, experts in geology have reached a broad consensus: the earth is approximately 4.5 billion years old. The consensus is strong; you will find vanishingly few geologists who posit, for example, that the earth is only 10,000 years old. By contrast, experts in physics are not in broad agreement concerning the value of string theory: some think that string theory is likely to be proven correct over the next few decades; others think not. Whether you discover consensus or division, ask yourself this question: to what degree does it exist? In other words, how strong or weak does it appear to be? Is it on a matter central to the discipline, or is it peripheral?
- If you become aware of an expert expressing an opinion not shared by the vast majority of experts in a field, bring closer scrutiny to the expert (for some experts are more likely to be right than others). For example, is he or she widely known and respected by peers, broadly published, and teaching at an esteemed institution (like Harvard)? Nobody is perfectly objective (obviously), but is there any reason to think that something other than the truth is driving this particular expert’s conclusions (financial interest, attention-seeking, strong political or religious motivation, senility etc). Also, ask yourself whether this person is actually speaking to a matter in which he or she is, in fact, an expert. For example, an astronomer offering an opinion on the value of childhood vaccinations is no more an expert in that subject than you are.
- Even if you have not been to China, you can nevertheless be confident (on reliable testimony) that China exists. Likewise, a consensus of experts in a field like physics can give you equivalent confidence that Einstein’s theory of relativity is true. You may not directly or clearly understand how experts arrive at their consensus concerning relativity, but you can treat it exactly as you do China, as part of your background knowledge. Here is a good rule-of-thumb: wherever scientific expert consensus exists, you are warranted in giving it strong belief; where opinion is divided, agnosticism is warranted; and where you are entertaining an expert’s minority viewpoint that sounds plausible to you, you are (perhaps) warranted in apportioning a small amount of cautious belief to it.
- Academic endeavors, as social endeavors, are not perfect processes, and some disciplines are far more empirical than others (compare medicine to history). If you have good reasons to believe that an expert consensus is skewed by such things as inertia, peer pressure, source funding, insufficient empiricism, or cultural bias, you are warranted in discounting it accordingly. Keep doubt alive. But experts should be grappled with, never ignored.