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

by Steven Novella

A hypnagogic episode is like a brain glitch—it’s stuck between two states. The biggest problems come from assuming that the phenomenon is a reflection of external reality rather than an internal experience happening in the brain.

The real lesson from our knowledge of hypnagogia is that we can’t assume our brains are always functioning flawlessly and therefore whatever we think we experienced must be real.

The ideomotor effect is an involuntary subconscious subtle muscle movement driven by expectation, which creates the illusion that the movement is due to an external force.

If someone is able to show me that what I think or do is not right, I will happily change, for I seek the truth, by which no one was ever truly harmed. It is the person who continues in his self-deception and ignorance who is harmed. —Marcus Aurelius

The Dunning-Kruger effect describes the inability to evaluate one’s own competency, leading to a general tendency to overestimate one’s abilities.

The greatest enemy of knowledge is not ignorance—it is the illusion of knowledge. —Daniel J. Boorstin

In a 2014 article discussing his now famous paper, Dunning summarized the effect: “Incompetent people do not recognize—scratch that, cannot recognize—just how incompetent they are.”

What’s curious is that, in many cases, incompetence does not leave people disoriented, perplexed, or cautious. Instead, the incompetent are often blessed with an inappropriate confidence, buoyed by something that feels to them like knowledge.

The core of the effect, however, seems to be what Dunning describes: Ignorance carries with it the inability to accurately assess one’s own ignorance.

An ignorant mind is precisely not a spotless, empty vessel, but one that’s filled with the clutter of irrelevant or misleading life experiences, theories, facts, intuitions, strategies, algorithms, heuristics, metaphors, and hunches that regrettably have the look and feel of useful and accurate knowledge.

Admit it: Up to this point in the chapter, you were probably imagining yourself in the upper half of that curve and inwardly smirking at the poor rubes in the bottom half. But we are all in the bottom half some of the time. The Dunning-Kruger effect does not just apply to other people—it applies to everyone. That’s why the world is full of incompetent, deluded people—we all are these people.

Here comes the critical part: Now realize that you are as ignorant as the average person is in every other area of knowledge in which you are not expert. The Dunning-Kruger effect is not just about dumb people not realizing how dumb they are. It is about basic human psychology and cognitive biases. Dunning-Kruger applies to everyone. In addition to the various aspects of critical thinking, self-assessment is a skill we can strive to develop specifically. But a good rule of thumb is to err on the side of humility. If you assume that you know relatively less than you think you do and that there is more knowledge than you are aware of, you will usually be correct.

Motivated reasoning is the biased process we use to defend a position, ideology, or belief that we hold with emotional investment.

Some information, some ideas, feel like our allies. We want them to win. We want to defend them. And other information or ideas are the enemy, and we want to shoot them down. —Julia Galef

We all have narratives by which we understand the world and our place in it. Some narratives are critical to our sense of identity. Preferred narratives support our worldview, our membership in a group, or our self-perception as a good and valuable person. We have narratives and beliefs that serve our basic psychological needs, such as the need for a sense of control. When those beliefs are challenged, we don’t take a rational and detached approach. We dig in our heels and engage in what is called motivated reasoning. We defend the core beliefs at all costs, shredding logic, discarding inconvenient facts, making up facts as necessary, cherry-picking only the facts we like, engaging in magical thinking, and using subjective judgments as necessary without any consideration for internal consistency. Collectively, these processes constitute motivated reasoning, something at which humans generally excel.

There is also a need to remind ourselves that people who disagree with us are just people. They are not demons. They have their reasons for believing what they do. They think they’re right just as much as we think we are right. They don’t disagree with us because we’re virtuous and they are evil. They just have a different narrative than we do, one reinforced by a different set of facts and subjective judgments. This doesn’t mean that all views are equally valid. It does suggest we should strive to focus on logic and evidence, not self-serving assumptions of moral superiority.

A logical fallacy is an invalid connection between a premise and a conclusion, where the conclusion does not necessarily flow from the premise(s) but is argued as if it does.

I am convinced that the act of thinking logically cannot possibly be natural to the human mind. If it were, then mathematics would be everybody’s easiest course at school and our species would not have taken several millennia to figure out the scientific method. —Neil deGrasse Tyson

logic and arguments should be used as a tool, not a weapon. When logic is used as a weapon, it’s far too easy to twist it subtly to suit one’s ends.

Another type of premise error occurs when one or more premises are unwarranted assumptions. The premise may or may not be true, but it hasn’t been established sufficiently to serve as a premise for an argument.

The third type of premise difficulty is the most insidious: the hidden premise. Obviously, if a disagreement is based upon a hidden premise, then the disagreement will be irresolvable. So, when coming to an impasse in resolving differences, it’s a good idea to go back and see if there are any implied premises that haven’t been addressed.

The fourth potential problem with premises, one that can be very subtle, is when a premise contains a subjective judgment. You might take as a premise that a particular news source is reliable. It is reliable according to what criteria and whose judgment? Subjective evaluations too easily allow for tweaking the premises to fit the desired conclusion.

Non Sequitur From Latin, this term translates to “it doesn’t follow,” and it refers to an argument in which the conclusion does not necessarily follow from the premises.

Argument from Authority The basic structure of such arguments is as follows: Professor X believes A, Professor X speaks from authority, therefore A is true.

Casually dismissing a solid scientific consensus as an “argument from authority” is a misuse of the logical fallacy. It is also an excellent example of how important context is in evaluating informal logical fallacies.

Argument from Final Outcome Such arguments (also called teleological) are based on a reversal of cause and effect, because they argue that something is caused by the ultimate effect that it has or the purpose that it serves. Christian creationists have argued, for example, that evolution must be wrong because if it were true it would lead to immorality (also a false premise).

Post Hoc Ergo Propter Hoc This is perhaps the most common of logical fallacies. It follows the basic format of A preceded B, therefore A caused B, assuming cause and effect for two events just because they are temporally related (the Latin translates to “after this, therefore because of this”).

Confusing Correlation with Causation This is similar to the post hoc fallacy in that it assumes cause and effect for two variables simply because they occur together.

To illustrate this, there is a website made by Tyler Vigen called Spurious Correlations.

This abuse is captured in the oft misquoted phrase, “Correlation does not imply causation.” Well, in fact it does imply causation and may be due to a particular causation—sometimes A does cause B. A better quote would be that correlation does not necessarily imply causation, or that it does not, alone, prove causation. But it is one line of evidence for it.

Special Pleading, or Ad Hoc Reasoning This is a subtle fallacy, often difficult to recognize. In essence, it’s the arbitrary introduction of new elements into an argument in order to jerry-rig that argument so it appears valid.

ad hoc (literally, “for this”)

Carl Sagan gave perhaps the most famous example of this fallacy in his “invisible, floating, incorporeal, heatless dragon in his garage” argument. Essentially, he claims that there is a dragon in his garage, and then invents a special reason why each test for the presence of the dragon fails.

Tu Quoque The Latin phrase tu quoque translates to “you too.” This is an attempt to justify wrong action because someone else does the same thing: “My evidence may be bad, but so is yours.” This fallacy is frequently committed by proponents of various alternative medicine modalities, who argue that even though their therapies may lack evidence of effectiveness, more mainstream modalities also lack such evidence. That argument, of course, doesn’t justify a treatment that lacks evidence.

Ad Hominem An ad hominem argument is one that attempts to counter another’s claims or conclusions by attacking the person rather than by addressing the argument itself. True believers will often commit this fallacy by countering the arguments of skeptics with statements that skeptics are closed-minded

If I impolitely state that someone with whom I disagree is a jackass, that’s not an ad hominem logical fallacy. If I say their argument is wrong because they are a jackass, then that is a fallacy. But they may still be a jackass.

Skepticism isn’t closed-minded, and the opposite of skepticism is not open-mindedness (it’s gullibility).

being open-minded also means being open to the possibility that a claim is wrong. It doesn’t mean assuming every claim is true or refusing to ever conclude that something is simply false. If the evidence leads to the conclusion that a claim is false or a phenomenon does not exist, then a truly open-minded person accepts that conclusion in proportion to the evidence. Open-mindedness works both ways.

Ad Ignorantiam The argument from ignorance basically states that a specific belief is true because we don’t know that it isn’t true.

Often the argument from ignorance is defended with the adage “Absence of evidence is not evidence of absence.” While this sounds pithy, it’s not strictly true. Absence of evidence is, in fact, evidence of absence. It’s just not absolute proof of absence.

You can’t ever prove a negative, but the more you look for something without finding it, the less likely it is to exist.

in order to make a positive claim, positive evidence for that specific claim must be presented. The absence of another explanation only means that we don’t know—it doesn’t mean we get to make up a specific explanation.

Confusing Currently Unexplained with Unexplainable Because we don’t currently have an adequate explanation for a phenomenon does not mean that it’s forever unexplainable or that it therefore defies the laws of nature or requires a paranormal explanation.

False Continuum A false continuum is the idea that because there is no definitive demarcation line between two extremes, the distinction between the extremes is therefore not real or meaningful.

False Dichotomy This fallacy involves arbitrarily reducing a set of many possibilities to only two. For example, evolution isn’t possible, so we must have been created (which assumes these are the only two possibilities). This fallacy can also be used to oversimplify a continuum of variation to two black-and-white choices. Science and pseudoscience are not two discrete entities, for instance; the methods and claims of all those who attempt to explain reality fall along a continuum from one extreme to the other.

False Analogy A false or faulty analogy consists of assuming that because two or more things are similar in one way, then they are also similar in some other way, ignoring any important distinctions between the two.

False analogy can be a very subtle logical fallacy. You must always ask the question, Are the things being compared truly analogous, and even if they are analogous in some ways, are they analogous in the specific ways that are being claimed?

Our brains operate largely by pattern recognition, and we frequently try to understand the novel by comparison to the familiar. Such comparisons are extremely useful, as is seeing commonality among disparate phenomena in order to perceive an underlying pattern. The trouble is that we’re too good at pattern recognition and may see patterns where they don’t exist.

There is a flip side to this fallacy—denying a legitimate analogy because the two things being compared are not the same in every way. A valid analogy means that two things are similar in an important way relevant to the argument at hand. It doesn’t mean they are identical.

Genetic Fallacy The term “genetic” here doesn’t refer to DNA or genes but to origins. This fallacy consists of arguing against something because of where it came from, rather than considering whether or not it is valid in its current form.