Sunday, July 26, 2020

Differentiate Positive Claims and Normative Claims

Something that has annoyed me in recent months is the unwillingness to distinguish between positive and normative statements. A positive statement is a claim about how the world actually is, a factual claim. It is either true or false, and some evidence can be brought to bear on whether it's true or not. A normative statement is a claim about what we ought to do, a "should" statement. Famously, you can't get an "ought" from an "is." Of course, you can inform your normative statements with facts and evidence and logical arguments. But facts and logic don't do anything by themselves. They require some kind of value judgment to get to a statement of what we ought to do.  

For a clear example of people missing this distinction, think about the people who were talking about "the science" or "the experts", possibly "the facts", with respect to lockdown policy. It wasn't always clear what was being claimed, but the insinuation was always that "the Science (TM)" supported government policy that shut down schools and businesses. This isn't actually possible. Science alone can certainly inform policy. It can highlight trade-offs. An epidemiologist can tell you what's likely to happen under different scenarios, given different models of how a virus is likely to spread under different sets of policies. A virologist might be able to tell you whether a particular vaccine is likely to work, or she might be able to tell you if a vaccine might be unlikely for this virus. But in the end, picking policy depends on some kind of value judgment, which is inherently beyond the realm of the scientific. 

In rare cases, it might be the case that some policy is so overwhelmingly favorable compared to another. Suppose the options were: "With no lockdown, 99.9% of us die. With a strict lockdown, 99.9% of us live." In this case it might be a no-brainer. Basically everyone's values would pick the strict lockdown. In the real world, policy questions are more complex. There is vast uncertainty about the effectiveness of various policies. How much do people modify their own behaviors in the absence of an official government-approved lockdown? What is the effect at the margin of governments making it illegal to do certain activities? Those are still positive questions, even though the answer is shrouded in uncertainty. There is an answer, even if we can't know it. But then we get into normative questions. How should we weigh the loss of freedom against loss of life? People can adjust their own levels of caution, indulging or eschewing risky activities. What is the duty of the non-vulnerable (who are likely to take risks and possibly spread the virus) to the vulnerable (who are more likely to isolate themselves)? Can the vulnerable impose restrictions on the non-vulnerable, using the political system? This is a question of values, not of science. "The Science" does not give policymakers such stark, simple choices as the hypothetical above. 

Very recently, a group of health professionals signed a statement saying it was alright to protest the George Floyd killing, but not okay to protest the lockdown itself. (I already expressed my frustration over this in a recent post.) It's fine for someone to hold this opinion, but they are abusing their credentials as experts, as doctors, as public health professionals. By signing this letter "as health professionals" they are inherently appealing to scientific expertise, but they are using that expertise to make value judgments (normative claims). They need to be clearer about the distinction between a value judgment, which they are no more qualified to make than anyone else, and a scientific judgment about how the world is, which they are particularly qualified to make. Lay people will use their letter as a voice of authority to justify various policy responses, in this case shutting down some kinds of protests and permitting others. But no such authority to exists to make that distinction. As I said before:

I'm just noticing this now, but they were actually still condemning the prior protests in the statement that supported the new ones. This is bizarre. The virus does not care if the thing you're protesting is a worthy cause or not, so the public health recommendation for both should be the same. One possibility is that public health professionals got together and conducted a thorough cost-benefit analysis. They determined that precise effect of both kinds of protests on public health, somehow quantifying the likelihood of each protest to affect public policy and also quantifying the effect of those new policies on various morbitities and mortalities. No such study was ever done, of course.

Another example that applies to recent months is the question of surge pricing, sometimes referred to as "price gouging." I wrote this post pointing out the asymmetric outrage over some prices falling (like gas prices) and others rising (as face masks and soap and toilet paper should have). I shared it on social media, and got a blathering response from a relative who utterly missed the point. It might be more productive to separate this into two different propositions.
  1. If we repeal anti-gouging laws and allow prices to rise, it will solve the shortages.
  2. We should repeal anti-gouging laws.
The first is a positive statement. It's a statement about how the world works. I think people who respond viscerally to price increases need to be confronted with this as a purely factual question. Get them to answer the simple question: Would an economy with freely adjusting prices mean there are more essential goods available? First establish a framework for how the world is. If someone says "No", they are claiming something absurd. They are claiming that producers won't respond to a price increase by supplying more. Aren't these the greedy business people we all hear about, for some reason foregoing the option to make more money? Wouldn't the resulting increase in supply eventually bring the price back down to a manageable level? Likely, close to the pre-crisis level? Given that you have to either ration via price or via queuing (waiting in line), isn't it better to use the method that results in more people getting the goods and services (pricing)? They are repealing the laws of economics in their own minds. (And, in this case, it's not "economics" as some abstruse mathematical science, but common sense restated with some scientific rigor.) 

The second statement is a normative statement. Note the "should". You could in principle agree with 1) and still disagree with 2). Maybe someone believes that the perceived unfairness leads to so much resentment it would cause civil unrest. Or maybe someone is so committed to equality as a matter of values that they don't tolerate obnoxious price increases, even if it means fewer people die from the pandemic (because of less availability of masks, less available soap and hand sanitizer, etc.). That's fine, we could then have a discussion about values. We could hold that person's values up to a mirror and question whether they really believe them. We should ask questions that gauge the person's values. How many lost lives are you willing to tolerate for the sake of equality? (Another positive question has snuck into this conversation. Suppose this person thinks high prices means "only the rich" will get essential supplies. That is a proposition about how the world is. The proposition that "such a state of affairs is unfair" is a value judgement. In my opinion, this "the rich buy everything" scenario is implausible in the extreme. As I point out in the previous post about price gouging, I have never seen evidence that the extra money spent on the higher-priced goods represents a substantial fraction of anyone's household budget. There's plenty of room to adjust other expenditures. "Adjust your behavior and spending patterns" is exactly what changing prices tell us what to do. Censoring the information necessary to make those adjustments, as anti-gouging laws do, is incredibly destructive.)  

We might take a similar approach with the minimum wage, which is yet another example of government price fixing. There is a positive question: "Does a higher minimum wage cause some low-wage workers to lose employment?" The best research with the most detailed data set of workers' actual wages suggests a clear "Yes," consistent with economic theory and common sense. If you read them carefully, even pro-minimum wage economists answer this question with a qualified "Yes." But some people answer "No." They've heard the state of minimum wage research inaccurately summarized as "minimum wages don't cause unemployment." If that's you're starting point, it's probably hard to be against the minimum wage. But the positive question is separate from the normative question: "Should we raise (or lower) the minimum wage?" You can think that minimum wages cause some job loss, but that the winners win more than the losers lose. It's a value judgment to say that justifies such a policy change. (In the crude version of this argument, the minimum wage is a perpetual motion machine.) Or you could conceivably admit that all the negative employment effects of the minimum wage are very real and very nasty, but that offering a wage below some level is inherently immoral. In my experience, people shift so freely between the positive claims and the normative claims that it's impossible to nail them down. But it's worth trying to inject this distinction into the conversation. If you can first get someone to admit that a likely effects of a policy (the positive question) are X, Y, and Z, and that X, Y, and Z are widely agreed to be bad (the normative question), that's a good start. 

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I will briefly try to defend the experts who make "should" claims. It's possible that, for example, a doctor has an advantage over his patients in integrating all of his knowledge into a single decision. She could simply state all the likely consequences of the patient undergoing a given surgery, give various statistics about recovery rates and financial costs, and leave the patient to think it through for himself. But she could also make basic assumptions about the person's desires and values, perhaps assuming the patient is typical. "If I were the  patient..." or "If it were my child..." (In my own life, I recently had a veterinarian say, "If it were my cat...", and I found her frank advice useful. She was in effect telling me what I should do, in addition to informing me about possible treatment options.) This might be a good way to integrate a lot of information that the average patient finds hard to digest. The patient might be in a mood to say, "Don't give me a literature review. Should I have the surgery or not?" 

That's all fine. What I object to is the public health establishment deciding what outcome they want and then framing their presentation of "the science" to get that outcome. (Or, just as bad, taking their cue from political leaders and framing the science to suggest we "should" pursue an already chosen policy.) The public health ideology is often one of ignoring any trade-offs and increasing life expectancy at all costs. The only thing this cartoon gets wrong is the caption. They often sneak normative judgments into their recommendations, overruling our actual preferences. They are inherently opposed to opioids, smoking (vaping even), trampolines, and any other way of converting life-years into fun. They should at least be self-conscious about it. 

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