In a comment, Akshar asked, “As a lay person one of the question I have always had in my mind about economics is that how exactly should I separate good opinion from bullshit vending. … If as a layman I can’t tell the difference between informed opinion on economics v/s Bullshit why should I take Mr. Atanu Dey more seriously or why should I waste my time supporting Milton Friedman’s ideas.”
It is an unalterable fact of life that since time is a scarce resource we have to rely on others for most of what we value, whether physical or non-physical. We don’t have the time to discover for ourselves all the truths of mathematics, the laws of physics, the facts of nature; or invent technology (i.e., how to do things), grow food, build houses, engineer machines, make clothes, and so on. Given the limitations of time and cognitive abilities, we depend on trade and the division of labor that it entails. Each of us specializes to some degree. What I earn by writing code I exchange for everything else I need.
So how do I choose from among what’s on offer? As it happens, there are institutions in society that help in this regard. For most goods and services, we reply on the markets for signaling quality. If something continues to appeal to a large number of consumers for extended periods of time, it is probably OK for me. And of course my own taste guides me to choose among the many alternatives.
Some Things Don’t Matter
But what about things that I don’t know anything about? For those, I have to rely on recognized experts in various intellectual fields and accept their opinions as authentic, authoritative and (at least provisionally) valid. What keeps those people honest? There are institutions and processes that ensure quality in scientific research, most importantly the peer review process. I can’t judge the work of a quantum physicist but his peers can, and they do. The peers have an incentive to reveal any BS that their own churn out. We can rely on their self-interest, if not their unalloyed desire to seek out the truth.
As it happens, accepting the opinions of experts in most fields of intellectual endeavor does not matter. The experts do what they do and our inability to judge the quality of their work makes no difference to us, and our assessment of them hardly influences them in turn. Experts and laypersons inhabit non-overlapping worlds. There are a few domains which are exceptions to this: climate science and economics are important examples.
Some Things Matter
For those fields, when experts disagree or have divergent opinions, the judgement of laypersons does matter because people’s opinions affect policies through the political process. If for example a large segment of the population believes that the government ought to do something (whatever that may be) about climate change, then it would materially affect what actually happens — the government may take extremely costly actions that don’t create net benefits. This is clearly not so in the case of, say, the differences among artificial intelligence experts because most people aren’t all that interested in the matter.
To my mind, the only domain where public perception of expert opinion seriously matters is economics. For instance, if enough people believe that socialism is a better alternative to a free-market economy, then the society would move towards socialism (which, in my expert opinion, would be disastrous) because politicians respond to public opinion. The good news is that hardly any expert would recommend economic nonsense but the bad news is that the public is ill-equipped to reject the opinions of people who pretend to be experts.
But all is not lost. Economics, unlike quantum mechanics or AI, is accessible. Any layperson can learn the fundamental principles with only a bit of time and effort. All that is required is the ability to follow simple logic, and consistently apply the principles in small steps. The principles, fortunately, are not that many. Nobel laureate Thomas Schelling reported that the celebrated Cambridge University economist, Peter Bauer, believed that “the number of things that economists knew that were true, important, and not obvious, was no more than the fingers on one hand.”
What I find most rewarding is that some true and important things of economics are non-obvious. When we first encounter them, our naive intuition declares them unlikely to be true. But with a bit of intellectual effort, we can overcome that and our intuition gets trained and it becomes obvious. After that “Aha!” moment, we become delighted (and even smug) that we know some secrets that are denied to others who are not as fortunate as ourselves.
DIY BS Meter
So here’s the answer to Akshar’s questions. Since we cannot buy an economics “BS Meter” at Amazon, we have to build our own. We have to, first, learn those first principles and be able to apply them with logical consistency. Then when someone makes a claim, we have to test that claim against the principles. If the claim fails anywhere along the logical consistency test, you can reject it; if the claim passes the test, then you have grounds for not rejecting the experts opinion — which could mean that you tentatively accept the opinion.
It takes time to calibrate your BS Meter. Test it on obviously false claims. Then when you come across a claim that is not directly testable by the BSM, you ask, “If this claim is true, what else must be true?” If A is true about the world, then logically it must be that B, C and D must be true too. If your BSM registers BS on any of B, C or D, you know that A is BS too.
I have noticed that with time, BSM gets very easy to use. You develop an intuition. Daniel Kahneman, the psychologist who won a Nobel Memorial Prize in Economics, talks about System 1 and System 2 modes of thinking. System 1 is when our thinking is fast, automatic, intuitive, unconscious. Your System 1 tells you the answer to “2 time 20”, or allows you to drive a familiar route.
System 2 is the slow, effortful, logical, conscious mode of thinking. It gives you the answer to “17 times 29”, or when you have to make a complex comparison. Experts are experts often because their System 1 can handle what novices require their System 2 to handle.
I have been learning the fundamental principles of economics for around three decades. Almost without thinking, I can detect BS as fast as it is uttered. My immediate reaction is “are you retarded or are you just putting me on?” The detection is automatic using System 1. Explaining why it is so does require System 2. I am lazy and that is why I often give up on the explaining.
It’s all karma, neh!
Postscript: So what are those “fundamental principles”? I have outlined the method for free. The principles are not free. There is a $2.99 charge. (There used to be a tip jar on the main page. I will have to put that up again.)
 What do Economists Know? Thomas C.Schelling. Commencement address to the Dept of Economics, UC Berkeley, CA. May 1994.
 Thinking Fast and Slow. Daniel Kahneman. 2011. If you have not read that book, you have a treat waiting for you.