Monday, January 21, 2008

Arguments from expertise

Stephen Law, David Friedman* (quoted approvingly by Andrew Sullivan) and The Uncredible Hallq talk directly and indirectly about the argument from expertise (a.k.a. the argument from authority). Friedman says:
Part of my skepticism with regard to the efforts of my fellow atheists to demonstrate how absurd the opposing position is comes from knowing a fair number of intelligent, reasonable, thoughtful people who believe in God--including one I am married to.
*Friedman's post talks about more than just the argument from expertise, but I'll leave his other points for later.

Stephen Law notes the weakness of the trope "Many leading philosophers are [religious] believers, so it can't be that unreasonable, can it?"

The argument from expertise as a justification for a belief is always a fallacy. If you agree with an expert about an issue without understanding her argument, then you are not really agreeing, because you don't understand what the expert is saying. Whereas if you do understand the expert's argument, then you agree with her on the basis of the argument itself, not her expertise. What one believes is inexorably bound up in how one believes it, because the arguments in favor of a proposition serve as part of the definition of that proposition.

An individual proposition doesn't have meaning on its own; a proposition always has meaning relative to some linguistic or theoretical context, and the justification of the proposition is part of that context. You cannot understand a proposition without understanding its context, including its justification.

Expertise as a fallacious justification for belief is different from expertise as a sound rational justification for action. I don't have to understand how my engine works to rationally justify paying my mechanic $1,000 to fix it. I neither believe her nor disbelieve her when she tells me the framistam is fershluggener. I don't understand her, and I don't care that I don't understand her. All I care about is that after I pay her $1,000, I'll be able to drive my car to work.

Expertise, though, is a poor basis for justifying even action. I don't really care where or even whether my mechanic went to school, and — since I don't understand engines — I have no way of judging directly how well she understands engines. What I do understand, though, is the reliability of the outcome. Regardless of what she does, whether she performs a scientific diagnosis or psychically heals the framistam with woo-woo crystal power, I can still evaluate directly whether or not I can drive the car to work when she's done. I don't really want her degrees and certifications; I want, rather, a guarantee: if I can't drive the car to work when she's done, I want my money back. Any useful indirect method of measuring "expertise" is really a method of measuring reliability, in terms I can understand.

When it comes to fields where reliability can't be measured at all — theology, philosophy, literary criticism — or fields where you can't measure reliability in a practical way — e.g. theoretical physics, the argument from expertise becomes entirely vapid. When you can't measure reliability, expertise has little utility. You either have to dig in and look at the arguments directly, or you have to profess pure agnosticism, regardless of the opinion of the experts.

Looking at the arguments directly, though, is not as hard as it seems. Most of the training that soi disant experts receive is focused on affording the ability to do original work in the field. But I don't have to be capable of doing original work to understand an argument, just as I don't have to be a concert pianist to appreciate Horowitz. I have a pretty good grasp of Quantum Mechanics, for example, even though I don't have a PhD in physics. I can't even contemplate doing original work in physics, but I can follow a physicist's argument for a concept, and thereby understand it directly.

Without appeal to the underlying arguments, I would have no way of even understanding, much less believing, a physicist when she says, "Light is both a particle and a wave."

I think expertise, especially without a corresponding notion of comprehensible reliability, has a corrosive effect on society. It's become too easy for someone to grind through a PhD program and then spout whatever bullshit he pleases. George W. Bush, for example, has a Master's degree — in Business Administration — and the guy can't operate a lemonade stand at a profit, much less the United States.


  1. Hi Larry,

    I do disagree, and think it is sometimes rational to believe on the authority of experts (besides in your "action" case). If we trust in the process that the experts use to come to a conclusion, in consensus with each other, it seems appropriate to also believe in that conclusion that they reached.

    I believe that evolutionary theory is better-supported by science than any of its rivals, even though I admit that there is much of it that I do not understand and I am personally unable to refute every objection every creationist ever presents. Still, biologists use professional, peer-reviewed journals to analyze their research while creationists do not, and there are far more pro-evolution scientists than (legitimate) creation scientists. If I simultaneously come across a pro-evolution argument that I cannot refute and a pro-creationism argument that I cannot refute, I think I am rational in disbelieving the pro-creationism argument and believing the pro-evolution argument, simply on the authority of the scientists and the method that they use.

    Do you think that is wrong then?



  2. It's not a matter of having to "refute every objection", it's about understanding what it is you believe.

    If a scientist says, "life evolved", and you "believe" him, without looking at the underlying arguments at all, the question is, what precisely do you actually believe?

    If you understand the arguments, you believe because you understand the arguments, not because of scientists' expertise.

    (Note that scientific reputation goes only to trusting the scientist to accurately report his data.)

    If you can't refute an objection, it's usually because you don't understand the objection (and it may well be incoherent). In which case, you're entitled to simply be lazy-agnostic about the objection itself, not the underlying proposition. You still prefer the underlying proposition because the scientists' argument that you do understand is more persuasive than the objection you don't understand.

  3. There are times (I doubt I am alone in this) where I come across someone's objection, and I do genuinely understand what their objection is but do not personally see any fault in it, but still believe that their objection is probably rooted in error. That is because the I consider the chances that professional, educated, knowledgeable evolutionary scientists in the relevant field "overlooked" in some way a particular flaw in evolutionary theory while the creationist realized it is vastly less likely than the chance that the creationist is simply wrong and the evolutionary biologists are right, even though I still do not know the specific fault with the creationist's argument.

    I am out of time at the moment, but will try to come up with a specific example a bit later to play around with.



  4. There's a conflation between conclusions and facts. Expertise doesn't have anything to do with facts; facts are those statements I would "naturally" or uncontroversially agree with.

    It's subtle different to talk about trust in reliability, rather than justification by expertise.

    Because of their reliability, I trust scientists are (usually) not lying to me or bullshitting me, intentionally or unintentionally. I can measure the reliability of someone to not lie or bullshit: Are they accurately representing the facts? Are they "forgetting" to mention important facts?

    On the other hand, because of their demonstrated unreliability — because cretinists have shown time and again that they will lie outright and withhold important information — I don't trust cretinist arguments. It's not worth even the time to understand them because I'm very confident they will at the very least omit some fact, and often simply flat-out lie.

    None of this, though, has to do with justification by expertise; it's still about trust in measurable, understandable reliability.

  5. I am a bit unclear on what you mean---

    You said:

    "There's a conflation between conclusions and facts. Expertise doesn't have anything to do with facts; facts are those statements I would "naturally" or uncontroversially agree with."

    What is a "conclusion" then? Exactly how is it different from a "fact" and would you ever believe a "fact" but disbelieve a "conclusion" or vice versa? If you would always believe or disbelieve them together, I do not see what the point is in separating them out.

    A more specific example anyway---

    I believe that the proposition "the Earth is on the order of 4.5 billion years old" is supported by science. I understand what that statement means, and while I have not personally undertaken any experiments to verify its accuracy, and it is not a proposition that 'I would "naturally" or uncontroversially agree with"' but I trust that it is true based on the fact that it seems widely accepted by the scientific community, and I trust in the process used by the scientific community.

    Sometimes I peruse YEC websites and they will make arguments for an Earth that is 10,000 years-old, and I am unable to immediately refute those arguments. Sometimes, the flaw in their arguments come to me sometime later (minutes, weeks, years) while I have more time to consider it and/or more background knowledge, and sometimes I never personally discover a flaw at all.

    Is it irrational of me then to still believe that the earth is 4.5 billion years old and not 10,000, simply because I trust in the process used by scientists, and the fact that a lot more of them exist that believe the earth is old than young?

    (I am going offline now, but look forward to continuing this sometime later.)



  6. Sorry to be so long responding, Brian; I was somewhat busy yesterday.

    On the one hand, I still think I'm on to something treating the argument from expertise as a true fallacy. On the other hand, based on your remarks, I think my original construction isn't as deep or precise as it could be. It'll require further work.

    Part of the problem is that I'm a really curious bastard. It burns me to accept some statement, any statement, without knowing how it's justified. But that's an emotional issue, not necessarily a rational issue.

    That being said, I want to, at least for the moment, address your "inability to refute" objection. I don't think "inability to refute" goes to my underlying argument.

    If you believe some proposition because of a specific argument, and someone proffers a counter-argument which you're unable to specifically refute, yet you still believe the original proposition, then you still believe the proposition on the basis of the original argument, not on expertise.

    By my original formulation, if you can't refute the counter-argument, you don't understand it well enough to believe it's actually wrong. Even if the experts deny the counter-argument without rebuttal, it seems more logical to be at best agnostic about the counter-argument.

    Since you're already persuaded by the original argument, which ex hypothesi you do understand, it seems reasonable to say that you're not persuaded to change your mind about what you do understand by something you don't understand.

    (Two subtle issues: "disbelief" is equivocal: It means "believe to be false" and "not believing one way or the other" (i.e. agnostic). Furthermore, one is never absolutely certain in these sorts of cases. If there's a counter-argument I don't understand well enough to rebut, it would be reasonable to not be absolutely certain about the original proposition and its argument, but since I'm already not absolutely certain on general principles, the counter-argument doesn't change anything.)

  7. Even if the experts deny the counter-argument without rebuttal, it seems more logical for you yourself to be at best agnostic about the counter-argument.

  8. That's a pretty good forumlation (after the clarification in thought in response to Brian).

    I'm always uncomfortable with the concept of "trust me I'm an expert" - I'd rather understand the underlying reasons than just go on trust, though obviously one can't know everything - so I like your formulation with the car - you don't trust the 'expert' you just make a contract that only requires you to pay if the car works.

    Your mention of understanding, experts, and quantum physics reminded me of a quote I remember being attributed to Richard Feynman to the effect that anyone who claims they understand quantum physics is either lying or crazy.

  9. barefoot bum said

    "If you believe some proposition because of a specific argument, and someone proffers a counter-argument which you're unable to specifically refute, yet you still believe the original proposition, then you still believe the proposition on the basis of the original argument, not on expertise.(emphasis added)

    The cases I am referring to are not cases where a person is convinced because of a specific argument, but entirely on the basis of the fact that the person perceives that the scientific community has already come to a consensus on the issue. This person trusts in the processes (peer-review, scientific method, etc.) used by the scientists, and so considers it rational to believe in the results that those processes generate, when everyone (all the scientists) familiar with the research are in agreement with one particular conclusion.

    Suppose that you are personally not knowledgeable enough with the procedures and equipment that scientists use to determine the age of the earth so that you could do it yourself if given all their equipment and told "Go." Should you still believe (as I assume you do) that the earth is 4.5 billion years old? If it is clear that the scientific community has generally come to a consensus that it is that age, I think it is rational for you to similarly believe it, even though you do not truly understand their mechanics in coming to that conclusion. You know that those scientists have been conducting their research and doing so with the peer-review process as other good scientists do.

    Suppose then that another well-credentialed scientist came along and said that they are wrong, and provided an argument that concluded that the earth is really 6 billion years old. You are not sufficiently familiar with the subject to be able to see any specific fault in her argument, and nothing about the everyday Earth that you observe could immediately disqualify it. If she tells you though that she has not submitted his argument for peer review and has no intention of doing so, then I think you are right to reject it without seeing the specific error in it. She is not using the process that other scientists are, that has worked well for so long in helping us learn about the world around us.


  10. Well, Brian, I have to say that your age of the earth counter example is a challenge to my original thesis, that a proposition cannot be understood if it's justification is not understood. It seems obvious that a person can understand "The Earth is 4.5 billion years old" without understanding how that statement is justified. Worse yet, as I do personally understand the justification, I must admit that the justification has not changed the meaning of the original proposition one bit.

    I still think the idea that you can't understand the proposition without understanding the justification is a good generalization, but it's not universal.

    I've been thinking about your comments carefully. One thing keeps nagging at me: If your belief is justified by a process, is the distinction between expertise and meta-argument meaningful? On the one hand a dissenting well-credentialed scientist is, at least in some sense, an expert. On the other hand, the argument from expertise can just as easily rely on the preponderance of expert opinion without seeming to do violence to the notion of expertise.

    On the gripping hand, perhaps we have sufficiently narrowed the validity of the argument from expertise precisely to those propositions the speaker is not particularly interested in?

  11. barefoot bum said:

    "On the one hand a dissenting well-credentialed scientist is, at least in some sense, an expert."

    A much, much weaker sense though. If 99% of the relevant experts in a field subscribe to position A and one scientist comes around that advocates position B instead, it does not make sense for a non-expert to appeal to the latter as if they held any equivalent weight.

    I see the whole point of appealing to an authority as being to discover that some issue of contention has been settled by the people best qualified and knowledgeable about the subject, which saves 2 disagreeing non-experts from having to go through all the textbooks, college courses, field work, etc. to resolve their dispute between them. Other people have already done all that work and found out which answer is right and which is wrong. Any disagreements that those non-experts then have remaining should be built on top of that as a premise.

    You may personally currently understand the specifics of how the age of the Earth is determined, but have you always understood it? At some point in your life, you must have been not very knowledgeable about the subject at all. If someone presented a sophisticated argument to you at that point, or before it, that the Earth is really just 2 billion years old, you likely would not have known how to refute it.

    Are there any scientific subjects that you, today, consider yourself especially ignorant of---but ones where you do not personally experience any of your "action" effects as a result of?

    I gave the age-of-the-earth example earlier. If the Earth was really 6 billion or 2 billion years old would we really be able to tell any difference in our daily lives, compared to our lives now under the belief that it is 4.5 billion years old? Nah. It would seem the same to us.

    Perhaps I have held this view for so long because, unlike you apparently, I am not particularly curious about the specifics and details. You might even call me lazy. :)



  12. Briefly---

    Barefoot Bum said:

    "On the gripping hand, perhaps we have sufficiently narrowed the validity of the argument from expertise precisely to those propositions the speaker is not particularly interested in?"

    I would disagree with that. It is "narrowed" to the fields the person is not knowledgeable about, for any reason, whether it be because she is uninterested in it, or is interested but not knowledgeable.

    A person cannot realistically be an expert in all scientific fields. Any time someone spends studying to eventually become an expert in mathematics is time they are not spending becoming an expert in geology. If they are studying to be an expert in astronomy, they are not spending that same time becoming an expert in oceanography. They may be interested in all of those subjects and more, but only have the ability, time, energy, and resources to be experts in a fraction of them. In the others, it makes sense for them to appeal to the people that actually have become experts.


  13. "The argument from expertise as a justification for a belief is always a fallacy. If you agree with an expert about an issue without understanding her argument, then you are not really agreeing, because you don't understand what the expert is saying. "

    I think that's clearly false. I accept the advice of my doctor on various things without knowing the evidence on which that advice is based. I can understand, at least approximately, the statement "taking these bills will make you less likely to die of a heart attack" without knowing anything much about the evidence on which the statement was based.

  14. David Friedman: I think that's clearly false.

    On the one hand, Brian63 has already convinced me that the argument from expertise is not always fallacious.

    On the other hand, I argue in the post that the example you employ in your comment is best viewed, strictly speaking, as an argument for action from reliability rather than an argument for belief from expertise.


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