The Skeptics' Guide to the Universe: How To Know What's Really Real in a World Increasingly Full of Fake

by Steven Novella

If you’re still not convinced and can’t wrap your head around it, that’s okay. Probability doesn’t come naturally to us humans. Keep in mind, though, that computer simulations running this scenario thousands or millions of times clearly show that switching doors increases the odds exactly as I’ve described. If you still refute this answer in the face of evidence like that, maybe you’re better off with the goat.

Any viable modern definition of materialism must include energy, forces, space-time, dark matter, and possibly dark energy—and anything else discovered by science to exist in nature. In this way materialism is really just a manifestation of naturalism, the philosophy that says that nature (in all of its aspects) is all there is—there is nothing supernatural.

Another way to look at it is this: If scientists discover that something previously believed to be supernatural exists, then it will become natural, as it will have been demonstrated to be part of nature. Some argue that materialism is therefore a useless tautology (a definition that references itself), but this misses the point. The definition of materialism is really more about method; it’s about testable causes that we can investigate scientifically. “Supernatural,” therefore, is untestable magic.

Philosophical naturalism is the metaphysical belief that nature is all there is, while methodological naturalism is proceeding as if nature is all there is while remaining agnostic about the deeper metaphysical question.

Does science require methodological naturalism? Yes. That philosophical fight was fought in centuries past—and the naturalists won. The fight is over. But the anti-naturalists want to resurrect it, and since they can’t win in the arena of science, they want to fight in the arena of public opinion and then in the legal and academic realms.

NAS [the National Academy of Sciences] is in agreement that science is limited to empirical, observable and ultimately testable data: “Science is a particular way of knowing about the world. In science, explanations are restricted to those that can be inferred from the confirmable data—the results obtained through observations and experiments that can be substantiated by other scientists. Anything that can be observed or measured is amenable to scientific investigation. Explanations that cannot be based upon empirical evidence are not part of science.”

the anti-materialist/anti-naturalist movement is really about changing the ground rules of science (refighting the fight they lost in the past) to include supernatural explanations, but this is impossible within the necessary framework of science.

The proposition that human beings are created in the image of God is one of the bedrock principles on which Western civilization was built. Its influence can be detected in most, if not all, of the West’s greatest achievements, including representative democracy, human rights, free enterprise, and progress in the arts and sciences.

A paradigm in science is relatively stable over a period of time, but it may suddenly shift to a new paradigm for quirky reasons. Here’s a critical bit: Postmodernism insists that evidence and ideas can only be evaluated within a paradigm, not between paradigms. The key question is this: Is one paradigm objectively better than another, and is there therefore real progress in science, or is it all subjective? The postmodernists claim it’s all subjective.

Thomas Kuhn

The principle of Occam’s razor, attributed to William of Ockham (1287–1347), states that when two or more hypotheses are consistent with the available data, then the hypothesis that introduces the fewest new assumptions should be preferred. In the original Latin, “Non sunt multiplicanda entia sine necessitate,” which translates to “Entities must not be multiplied without necessity.”

Occam's razor. fewest new assumptions

A UFO proponent once argued to me that Occam’s razor, which he defined as preferring the simplest explanation for any phenomenon, actually favors the theory that aliens are visiting the Earth. The presence of aliens could potentially explain cattle mutilations, crop circles, reports of sightings and abductions, and a host of other strange phenomena. Skeptics come up with a separate explanation for each of these things. One explanation—aliens—was far simpler, and therefore a good skeptic should accept claims of alien visitation.

Occam’s razor is a principle of logic that is often invoked but rarely properly understood, as in the case of this UFO enthusiast. It’s a useful rule of thumb to help clarify one’s thinking, not a strict logical necessity. Failure to understand Occam’s razor, however, can lead to very sloppy thinking.

Occam’s razor is often paraphrased as, “When there are multiple possible answers, the simplest should be preferred.” However, the direct quote from William of Ockham is this: “Numquam ponenda est pluralitas sine necessitate [Plurality must never be posited without necessity].”

Occam's razor

What a clinician shouldn’t do (and this does violate Occam’s razor) is introduce an entirely new disease or condition just to explain each individual sign or symptom of a patient.

Occam’s razor is ultimately all about probability. Every time you introduce a new element to an explanation or make a new assumption, you reduce the probability that your explanation is correct.

When someone follows what looks superficially like a scientific process but the quality is hopelessly low and the process is fundamentally flawed, or distorted to achieve a predetermined end, we call that pseudoscience.

pseudoscience

The challenge of drawing an objective line between the two is what philosophers of science call “the demarcation problem.”

Many scientists were independently wealthy gentlemen who made major scientific discoveries in basements or cottages that had been converted into laboratories, or by making basic field observations. Darwin, Galileo, and Newton all fit this mold. Today, the gentleman scientist is a rarity, although his image persists in the lay consciousness.

The lay, or amateur, scientist must be content to sit on the sidelines and learn about exciting scientific discoveries in those books, journals, and lectures that are designed to distill this information for the public.

hmm

private citizen can’t just fire up a particle accelerator in their backyard and make important discoveries in particle physics. Professional scientists understand that even for them it’s difficult to contribute meaningfully to a field even marginally outside their areas of expertise.

true though

There are, however, citizen scientist projects in which interested people can participate. You can classify galaxies, find Kuiper Belt objects, and fold proteins. Trained scientists are responsible for maintaining a rigorous procedure, however.

lol

knowledge isn’t necessarily constricting. It can also be liberating. The more one knows, the easier it is to learn more information. Knowledge provides intellectual tools that can be applied to the process of discovery. Also, knowledge of what is already known helps in evaluating the plausibility of new ideas.

knowledge

Claims Often Promise Easy and Simplistic Solutions to Complex Problems or Questions

pseudoscience

The most challenging aspect of popularizing science is often translating technical jargon into everyday language while minimizing the loss of precision and accuracy.

A scientific hypothesis must be falsifiable. If it isn’t, then it’s “not even wrong.” Being wrong in science is useful; it still helps us move toward the answer. Being not even wrong is worthless and is by definition not scientific.

They ask for evidence, and when that evidence is provided, they demand still more evidence. Nothing will ever satisfy them.

We still have many more details to learn about DNA. But—and here is the critical part—nothing we currently don’t know about DNA or will learn in the future can possibly change the basic fact that DNA is the primary molecule of inheritance.

Interesting

You can almost always find some scientists somewhere to disagree with even the most solid scientific consensus. I’ve argued that this is a good thing. Complacency can lead to stagnation in science, and it’s always good to have someone shaking the tree. But such dissent needs to be put into context. Sometimes it’s a genuine controversy and the science can go either way. Other times the science is solid and the dissent is insignificant.

Maintaining standards isn’t anti-freedom, but it is easy to misrepresent it as such and to portray all attempts at promoting high standards as “elitism.”

Creationists argue that accepting evolution will undermine belief in God and even result in moral decay. Global warming deniers argue that accepting the “alarmist” claims about climate change will result in a government takeover of private industry. I characterize this strategy as an argument-from-final-consequences logical fallacy—evolution is wrong because if it were true society would suffer.

This is an inherently flawed strategy. If you truly wish to advocate for a particular moral or ethical position, the worst thing you can do is tie that position to a false scientific conclusion. Doing so allows opponents to attack your moral position by attacking the pseudoscience to which you have anchored it. You are far better off acknowledging legitimate science and advocating for your moral position on moral grounds. If you ideologically favor free markets, don’t deny global warming, rather offer free-market solutions.

Wow

A p-value of 0.05 (a typical threshold for being considered “significant”) indicates a 5 percent probability that the data are due to chance rather than a real effect.

Except—that’s not actually true. That is how most people interpret the p-value, but that’s not what it actually says. P-values don’t consider many other important variables, like prior probability, effect size, confidence intervals, and alternative hypotheses.

Let me restate that: A study with a p-value of 0.01 may have only a 50 percent chance in an exact replication of producing another p-value of 0.01 (not the 99 percent chance that most people would assume). Put another way, people (even experienced scientists) tend to think of the p-value as a predictive value, but it isn’t. It was never meant to be. It’s only a smell test to see if the data are at all interesting or just random noise.

Let’s say that 1 percent of forty-year-old women have breast cancer. Let us further say that mammograms are 80 percent sensitive (they will come out positive 80 percent of the time with patients who actually have breast cancer). They are also 90 percent specific (they will be negative 90 percent of the time with patients who do not have breast cancer). These numbers are pretty good for a screening test.

Here is the question: What is the predictive value of a positive mammogram in a forty-year-old woman, or what are the odds that she actually has breast cancer because her mammogram was positive? With a 90 percent specificity you might be tempted to say 90 percent, but that would be wrong. The real answer is 7.5 percent. This is because 99 out of 100 forty-year-old women do not have breast cancer, so with a 10 percent false-positive rate there will be about 10 women out of 100 who test positive but don’t have breast cancer. Only about 0.8 of the 1 in 100 women who have breast cancer will test positive.

So, out of 100 women, 9.9 will test positive but be negative, and 0.8 will test positive and be positive. So if you are a forty-year-old woman and test positive, chances are much greater it’s a false positive (0.8 true positive / 10.7 total positive x 100 = 7.5%). This situation is analogous to the p-value. Having a p-value of 0.05 does not mean there is a 95 percent chance the hypothesis is true any more than a positive mammogram in a forty-year-old woman mean...

This means that we can’t know the probability that a hypothesis is true just from the p-value of one study. We need to know the plausibility of the hypothesis, and we need to know what all the other relevant studies showed. We call this a Bayesian approach—you take the new information, you add it to the prior existing information, and you come up with a new probability that the idea is true.

choosing when to stop recording data, what variables to follow, which comparisons to make, and which statistical methods to use—all decisions that researchers have to make about every study. If, however, they monitor the data or the outcomes in any way while making these decisions, they can consciously or unconsciously exploit their “degrees of freedom” to reach the magic p-value of 0.05. In fact, Simmons showed you can reach a p-value of 0.05 60 percent of the time with completely negative data. Simonsohn points out that p-values in published papers cluster suspiciously around the 0.05 level—implying that researchers were engaging in p-hacking until they reached this minimal publishable threshold.

P hacking

It’s likely that most p-hacking is innocent, meaning that the researchers don’t realize they’re essentially cheating. For example, if you survey the data as you collect it, you might decide that once you cross over the p = 0.05 threshold you can stop collecting data and publish.

The core problem with conspiracy thinking is that it’s a closed belief system, specifically designed to insulate itself from external refutation or even the need for internal consistency.

Any evidence that can potentially falsify the conspiracy theory is just part of the conspiracy. To the conspiracy theorist, such evidence was obviously fabricated in order to maintain the conspiracy. So, whether it’s a scientific study showing that vaccines are safe, high-resolution pictures showing that astronauts were on the moon, or evidence linking terrorists to 9/11—it’s all fake.

Any events that seem to contradict a conspiracy narrative were clearly a “false flag” operation: The government engineered the whole thing to throw the sheeple off track. Further, any evidence that we would expect to find to support the conspiracy but is missing is part of a cover-up. The conspirators are really good at covering their tracks. How good? As good as they need to be.

If George Bush faked the terrorist attacks on 9/11, why didn’t Democrats expose the conspiracy when they held the reins of power? They must have been in on it. Why hasn’t the media exposed the conspiracy either? They must be in on it too. What about other governments, many of whom are our enemies? Take a wild guess. Any problems with the conspiracy can be solved by simply expanding it. Before long, you get to the belief that a worldwide shadow government controls everything—the Illuminati, reptilian overlords, the New World Order, and similar grand conspiracies.

Lol so true

If you question their elaborate conspiracy theory, then you’re gullible and lack the vision to see events for what they are. If you point out the factual and logical problems with their case, then you’re clearly part of the conspiracy. You are a shill, or part of an “astroturf” campaign, or even perhaps one of the Illuminati.

They don’t have to provide evidence for the conspiracy, they can just poke holes in the standard version of events.

The sane understand that human beings are incapable of sustaining conspiracies on a grand scale, because some of our most defining qualities as a species are inattention to detail, a tendency to panic, and an inability to keep our mouths shut.

True

liberals and conservatives were more likely to accept a conspiracy if it was in line with their ideology. Meanwhile, for conspiracies without clear political implications, such as whether or not the government is covering up a crashed saucer at Roswell (21 percent overall believe this) or whether Paul McCartney was killed in 1966 (5 percent overall), belief is roughly the same across the political spectrum. There’s also no political difference when it comes to basic conspiracy ideology, such as the tendency to think there are powerful secret forces at work in the world.

In this area, ideas followed a typical historical pattern. At first, conspiracy thinking was seen as a form of psychopathology involving paranoid delusional ideation. More recently, conspiracy thinking is seen as fulfilling certain universal psychological needs perhaps triggered by situational factors.

To the extent that conspiracy theories fill a need for certainty, it is thought they may gain more widespread acceptance in instances when establishment or mainstream explanations contain erroneous information, discrepancies, or ambiguities (Miller, 2002).