Yet, I find many times, when these journalists digress from a specific subject, to science in general they are extremely naive or duplicitous. If you go to The Skeptic's Guide to the Universe, you invariably hear a bunch of caricatures of those who disagree with conventional wisdom on science—most of which truly are quacks, but not always—and they pedantically emphasize how these alternative views are 'not science': they have beliefs that do not have peer-reviewed tests supporting a falsifiable hypothesis. Or listen to Chris Mooney, a journalists who thinks the masses are insufficiently scientific, and argues that Republicans hate or are ignorant of science. He argues we should have more 'pro science' candidates, reflecting the 19th century progressive notion that with education, most disagreements and bad policy disappears. Most importantly, if the masses knew more, he surely thinks then popular opinion would converge to his. This from a journalist, a clan whose scientific proficiency is similar to the athleticism of mathematicians.
When journalists talk about science in general this is usually a pretext for saying those who disagree with their favorite idea are wrong, because they are unscientific. Who can be against science? There isn't a formal anti-science movement because it's indefensible in principle. They then caricature their opponents, taking the most inarticulate advocates from the other side, and skewering their illogic. They then sit back and take take inordinate pride in their scientific pretensions, as if their selective discussion was objective. The fact is, most 'big' scientific issues do not conform to the scientific method, where one puts out testable hypotheses, rejecting ones that are falsified.
Take finance, where the main potentially falsifiable theory is that there is a Stochastic Discount Factor 'like' the S&P500 index that one uses to generate 'risk', and thus the expected return, on every asset. This is a prerequisite for any rational portfolio allocation, because you need the mean for a 'mean-variance optimization algorithm' for determining one's portfolio. What is this Stochastic Discount Factor? Well, not the S&P500, though that's what is still taught in Business School via the CAPM, because we are pretty sure these betas are not correlated with returns cross sectionally anywhere. In Treasuries, it's a subset of forward rates. In equities, its a size, value, and market factor (the Fama-French factors), or it could be consumption-to-wealth ratio, where consumption is measured as nondurable consumption, and wealth comes from the Survey of Households. Or it could be year-over-year consumption growth. Bill Sharpe, who won the Nobel prize for his one factor model, also has a model with 12 factors. If it squiggles over time, it's a viable risk factor proxy. So, no one knows how to measure true risk, but presumably markets price it by aggregating everyone's preferences for this unidentified factor(s). Yet, as Andrew Lo states, "Finance is the only part of economics that works." Yikes!
To see how incredibly bizarre this situation is, consider the classic demonstration of group intelligence is the jelly-beans-in-the-jar experiment, in which the group's estimate is usually far superior to the vast majority of the individual guesses. When finance professor Jack Treynor ran the experiment in his class with a jar that held 850 beans, the group estimate was 871. Only one of the fifty-six people in the class made a better guess. So that's how risk and return work, the wisdom of crowds distills a precise truth out of our fuzzy uncertainty. Except here's the problem: no one know what risk is. It like presenting people with a jar of jelly beans, a jar of rice, a jar of rocks, and a jar of bb's, and asking them 'How many are in THE jar'? The question does not make sense; there can be no aggregation. So with respect to risk, if no one knows what it is after 40 years of searching, why should we think people agree on it sufficiently to aggregate and distill priced risk premiums. Is it any wonder we can't measure them?
Yet, if you ask financial economists how scientific their field is, you can be sure the answer will be some variation on very. For example, derivatives pioneer Mark Rubinstein paid homage to Modern Portfolio Theory creator Harry Markowitz in 2002, and noted that:
Near the end of his reign in 14 AD, the Roman emperor Augustus could boast that he had found Rome a city of brick and left it a city of marble. Markowitz can boast that he found the field of finance awash in the imprecision of English and left it with the scientific precision and insight made possible only by mathematics.This gives the impression finance is working on the third digit of fundamental constants in finance, as opposed to finding the right sign.
But, finance should be congratulated because its errors are more conspicuous than other fields, which have similar problems. Take String Theory. Invariably any researcher is working on one aspect of the theory, and cannot comment on the theory as a whole. Alas, the main problem is they have 10^500 potential solutions, and prominent theorists saying that these actually all exist now. One of them matches our universe, but with quintgoogle universes this is unsurprising. Throw in the anthropic principle, which states we necessarily live in a universe hospitable to human life, and there we are, numbers match to a T. It does not predict, it explains, but in a meager way because it merely tries to match parameters generated from a small set of separate models using a much more complex but unified model. Complex mathematics necessarily has more degrees of freedom, so this is all pretty unsurprising, and without some novel testable hypothesis, rather pointless.
Or take astrophysics. Their theories of the early universe also tell us which atoms should have been forged in the first 5 minutes after the big bang, and the existing amounts of hydrogen and helium match theory so well that cosmologists claim this is the best evidence we have for the big bang. Yet what about the next element, lithium? There, they are off by a factor of three. They don't like to talk about that. Or background of the universe, which seems perfectly flat...except for this mystery pattern in the middle called the 'axis of evil' that does not make any sense.
But the best example of science putting lipstick on a pig is dark matter. Vera Rubin, together with Kent Ford, announced at a 1975 meeting of the American Astronomical Society the astonishing discovery that most stars in spiral galaxies orbit at roughly the same speed, which implied that their mass densities were uniform well beyond the locations with most of the stars (the galactic bulge). This result suggests that either Newtonian gravity does not apply universally (can't be) or that most of the mass of galaxies was contained in the relatively dark galactic halo. Met with skepticism, it is now conventional wisdom. But what is dark matter? The stuff needed to make Newtonian physics match galaxial reality. It's like saying X=7, but when you measure X=9, you simply say there is an extra '2' of 'dark X'. They've tried to find it, building big swimming pools underground, hoping to find evidence of the leading candidate for dark matter (WIMPS), but thus far have been no more successful than SETI.
Or take our solar system, where every planet except Jupiter is assumed to have a huge, fortuitous asteroid giving it its singular properties of spin, moon, or composition. It seems like it is more common than not to fix a flawed empirical prediction with a nonfalsifiable adjustment.
Lastly, take Darwinian evolution, the idea that all life on earth descended from a common ancestor. Now, if you define evolution as the natural processes of heredity, chance, mutation, and natural selection, I believe 100% in evolution. That is, methodological naturalism excludes any other possibility. If you don't believe in the supernatural, evolution is a tautology because whatever exists descended from something else that was both lucky and successful, statistically, and also different from but related to its ancestors. The real theory in evolution, is the mechanism, which is on much shakier ground, similar to economists understanding of business cycles.
Take the 'evidence' for evolution, which has been assumed overwhelming by conventional scientific opinion for over a century, and see how tendentious it is. Darwin thought his best evidence was Haeckel's drawings that suggested ontogeny recapitulates phylogeny, that species closer to our uber-ancestors look more like early embryos, species higher in the evolutionary tree like late embryos. We know know those drawings were frauds, and this line of reasoning is a dead end. Karl Popper gave as an example of the analytical power of evolution the existence of darker moths in industrial environments, and this example was prominent in textbooks for decades. But the signature pictures of the dark moth on the pollution-darkened tree were invariably stuck there with a pin, and not relevant to speciation. Or Darwin's famous finch beaks, that were longer when there was less food--these turned out to be temporary phenomenon, and there is no trend in finch beaks that suggests this phenomenon leads to speciation.
Darwin anticipated finding all sorts of intermediate forms in evolution, but these are the exception, not the rule. Indeed, Gould's punctuated equilibrium theory was first seen as untrue, but then, a minor change in emphasis that Darwin's theory allowed all the time. There is much effort to show Darwin did not reject sudden changes, but clearly the Origin of Species emphasized the smaller steps. One can argue that 'sudden' in geological time is long in generations, but nonetheless, it's a major change in emphasis. The scientists like to whitewash these debates because they are scared to death of looking uncertain to Bible thumpers.
Or take Richard Dawkins, whose Selfish Gene argued evolution takes place almost entirely at gene level (ergo, selfish gene, not selfish organism), not the organism or the population. Over the past 15 years this view is now very much in doubt, as evolution at multiple levels appears equally important, with no special prominence to the gene level. Emphasis is everything because science is about probabilities, not possibilities, and so Dawkins was wrong, though he has never admitted to anything but being right all along.
The smoking gun for evolution from common descent is speciation, not local adaptation and differentiation of populations. There is no smoking gun. The mechanism of evolution is still a mystery, unless one is happy merely knowing that it's 'not God', which given methodological naturalism, is true by assumption. Nonetheless, none of these setbacks has affected believers in the theory of evolution, which even in its very incomplete state of explanation is considered perhaps the greatest scientific theory of all time. In sum, there is no debate about the tautologous portion of evolutionary theory, but mass mystery on the 'scientific' part, though they are loathe to admit it.
In all these cases, science mainly is about explanation, not prediction, and practitioners exhibit much more precision and confidence than is objectively warranted. Even in cases where there is prediction, like Global Warming, this is not falsifiable prediction. There are not unambiguous Global Warming forecasts with standard errors, such that in one's lifetime any Global Warming advocate could be proven wrong. If the world shows no trend in temperatures, it will simply be seen as temporary. There are no definitive tests in major scientific debates.
So, when some journalists talks about how horrible it is that politicians, or voters, do not understand science, which their rigorous falsification of hypotheses, I say, gimme a break. The biggest scientific debates are not about testing a definitive hypothesis, they are more often about coming up with more evidence for a metaview about some bigger truth, hardly much different than our quaint medieval ancestors. The big ideas are fun to think about, and I have opinions on them, but I'm not naive enough to think these debates are subject to the ideals of THE scientific method, where only objective, rational empiricism is involved. Tests that don't go our way are dismissed, tests that favor our predisposition are emphasized.
If you don't think that is true, think about how many Keynesian economists became supply siders over their career, or supply siders who became Keynesians. Think about the market efficiency debate, where irrationalists (eg, Thaler, Shliefer, Stiglitz) are against those who see the markets as rational (eg, Fama, Cochrane, and French). I would estimate less than 5% of economists change sides over their working lives. Yet, they are all scientists, use logic, examine data, publish in peer reviewed journals, understand statistics, and generally think they have good faith trying to understand the world as it is. The data seem rather unconvincing to diametric views on the big ideas within any field.
God is dead, but faith did not disappear. Rather, people always have faith in whatever they think is really important. With God out, now what is important is some big cause that, when fixed, will create a better world. As Eric Hoffer noted in The True Believer, 'all mass movements are interchangeable', meaning nationalistic, religious, social, political movements have the same true believers. Western civilization has tossed off nationalism and religion, but we are just as ideological as ever, only now we pride ourselves that our beliefs in social or ecological justice as the result of truth, divined through science. If only.
It is good to have the facts on your side because it makes it a lot easier to argue your case, but in real time any big debate necessarily will have ambiguous facts for the simple reason that if the data were definitive there would not be a debate. Further, important matters necessarily have a debate, because there if there's no debate one takes it for granted, as opposed to seeing it as something noble to fight for. In this cynical view of the world, it is best to have common sense, which Einstein said 'is nothing more than a deposit of prejudices laid down in the mind before you reach eighteen.'
Science as a practical matter is about applying logic to data piecemeal. Isaac Newton made huge contributions to optics, and created calculus so he could prove the laws of motion. He also had bat-shiat crazy ideas about alchemy and Biblically based numerology, and thought his greatest achievement was dying a virgin. And that's as good as it gets.
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