Among the 34 videos, you’ll find:

• Why do we need a belief in God?
• Why did you write The Believing Brain
• Do you think children should be taught to be more skeptical?
• Is there a psychological difference between open- and close-minded people?
• What are some of the strangest beliefs you’ve ever encountered?
• Is it possible to retrain our brains and belief systems?
• VIEW the entire playlist on YouTube.

Below is the second of the 34 videos. The entire series (total running time: 50 min. 32 seconds) can be viewed as a playlist on YouTube.

WAS PRESIDENT BARACK OBAMA BORN IN HAWAII? I find the question so absurd, not to mention possibly racist in its motivation, that when I am confronted with “birthers” who believe otherwise, I find it diffcult to even focus on their arguments about the difference between a birth certificate and a certificate of live birth. The reason is because once I formed an opinion on the subject, it became a belief, subject to a host of cognitive biases to ensure its verisimilitude. Am I being irrational? Possibly. In fact, this is how most belief systems work for most of us most of the time.

We form our beliefs for a variety of subjective, emotional and psychological reasons in the context of environments created by family, friends, colleagues, culture and society at large. After forming our beliefs, we then defend, justify and rationalize them with a host of intellectual reasons, cogent arguments and rational explanations. Beliefs come first; explanations for beliefs follow. In my new book The Believing Brain (Holt, 2011), I call this process, wherein our perceptions about reality are dependent on the beliefs that we hold about it, belief-dependent realism. Reality exists independent of human minds, but our understanding of it depends on the beliefs we hold at any given time.

I patterned belief-dependent realism after model-dependent realism, presented by physicists Stephen Hawking and Leonard Mlodinow in their book The Grand Design (Bantam Books, 2011). There they argue that because no one model is adequate to explain reality, “one cannot be said to be more real than the other.” When these models are coupled to theories, they form entire worldviews.

Once we form beliefs and make commitments to them, we maintain and reinforce them through a number of powerful cognitive biases that distort our percepts to fit belief concepts. Among them are:

ANCHORING BIAS: relying too heavily on one reference anchor or piece of information when making decisions.

AUTHORITY BIAS: valuing the opinions of an authority, especially in the evaluation of something we know little about.

BELIEF BIAS: evaluating the strength of an argument based on the believability of its conclusion.

CONFIRMATION BIAS: seeking and finding confirming evidence in support of already existing beliefs and ignoring or reinterpreting disconfirming evidence.

On top of all these biases, there is the in-group bias, in which we place more value on the beliefs of those whom we perceive to be fellow members of our group and less on the beliefs of those from different groups. This is a result of our evolved tribal brains that lead us not only to place such value judgment on beliefs but also to demonize and dismiss them as nonsense or evil, or both.

Belief-dependent realism is driven even deeper by a meta bias called the bias blind spot, or the tendency to recognize the power of cognitive biases in other people but to be blind to their influence on our own beliefs. Even scientists are not immune, subject to experimenter-expectation bias, or the tendency for observers to notice, select and publish data that agree with their expectations for the outcome of an experiment and to ignore, discard or disbelieve data that do not.

This dependency on belief and its host of psychological biases is why, in science, we have built-in self-correcting machinery. Strict double-blind controls are required, in which neither the subjects nor the experimenters know the conditions during data collection. Collaboration with colleagues is vital. Results are vetted at conferences and in peer-reviewed journals. Research is replicated in other laboratories. Disconfirming evidence and contradictory interpretations of data are included in the analysis. If you don’t seek data and arguments against your theory, someone else will, usually with great glee and in a public forum. This is why skepticism is a sine qua non of science, the only escape we have from the belief-dependent realism trap created by our believing brains.

After a public lecture in 2005, I was buttonholed by a documentary filmmaker with Michael Moore-ish ambitions of exposing the conspiracy behind 9/11. “You mean the conspiracy by Osama bin Laden and al Qaeda to attack the United States?” I asked rhetorically, knowing what was to come.

“That’s what they want you to believe,” he said. “Who is they?” I queried. “The government,” he whispered, as if “they” might be listening at that very moment. “But didn’t Osama and some members of al Qaeda not only say they did it,” I reminded him, “they gloated about what a glorious triumph it was?”

“Oh, you’re talking about that video of Osama,” he rejoined knowingly. “That was faked by the CIA and leaked to the American press to mislead us. There has been a disinformation campaign going on ever since 9/11.”

Conspiracies do happen, of course. Abraham Lincoln was the victim of an assassination conspiracy, as was Austrian archduke Franz Ferdinand, gunned down by the Serbian secret society called Black Hand. The attack on Pearl Harbor was a Japanese conspiracy (although some conspiracists think Franklin Roosevelt was in on it). Watergate was a conspiracy (that Richard Nixon was in on). How can we tell the difference between information and disinformation? As Kurt Cobain, the rocker star of Nirvana, once growled in his grunge lyrics shortly before his death from a self-inflicted (or was it?) gunshot to the head, “Just because you’re paranoid don’t mean they’re not after you.”

But as former Nixon aide G. Gordon Liddy once told me (and he should know!), the problem with government conspiracies is that bureaucrats are incompetent and people can’t keep their mouths shut. Complex conspiracies are difficult to pull off, and so many people want their quarter hour of fame that even the Men in Black couldn’t squelch the squealers from spilling the beans. So there’s a good chance that the more elaborate a conspiracy theory is, and the more people that would need to be involved, the less likely it is true.

Why do people believe in highly improbable conspiracies? In previous columns I have provided partial answers, citing patternicity (the tendency to find meaningful patterns in random noise) and agenticity (the bent to believe the world is controlled by invisible intentional agents). Conspiracy theories connect the dots of random events into meaningful patterns and then infuse those patterns with intentional agency. Add to those propensities the confirmation bias (which seeks and finds confirmatory evidence for what we already believe) and the hindsight bias (which tailors after- the-fact explanations to what we already know happened), and we have the foundation for conspiratorial cognition.

Examples of these processes can be found in journalist Arthur Goldwag’s marvelous new book, Cults, Conspiracies, and Secret Societies (Vintage, 2009), which covers everything from the Freemasons, the Illuminati and the Bilderberg Group to black helicopters and the New World Order. “When something momentous happens, everything leading up to and away from the event seems momentous, too. Even the most trivial detail seems to glow with significance,” Goldwag explains, noting the JFK assassination as a prime example. “Knowing what we know now … film footage of Dealey Plaza from November 22, 1963, seems pregnant with enigmas and ironies — from the oddly expectant expressions on the faces of the onlookers on the grassy knoll in the instants before the shots were fired (What were they thinking?) to the play of shadows in the background (Could that flash up there on the overpass have been a gun barrel gleaming in the sun?). Each odd excrescence, every random lump in the visual texture seems suspicious.” Add to these factors how compellingly a good narrative story can tie it all together — think of Oliver Stone’s JFK or Dan Brown’s Angels and Demons, both equally fictional.

What should we believe? Transcendentalists tend to believe that everything is interconnected and that all events happen for a reason. Empiricists tend to think that randomness and coincidence interact with the causal net of our world and that belief should depend on evidence for each individual claim. The problem for skepticism is that transcendentalism is intuitive; empiricism is not. Or as folk rock group Buffalo Springfield once intoned: Paranoia strikes deep. Into your life it will creep…

Long long ago, in an environment far far away from the modern world, humans evolved to find meaningful causal patterns in nature to make sense of the world, and infuse many of those patterns with intentional agency, some of which became animistic spirits and powerful gods. And as a social primate species we also evolved social organizations designed to promote group cohesiveness and enforce moral rules.

People believe in God because we are pattern-seeking primates. We connect A to B to C, and often A really is connected to B, and B really is connected to C. This is called association learning. But we do not have a false-pattern-detection device in our brains to help us discriminate between true and false patterns, and so we make errors in our thinking: a Type I error is believing a pattern is real when it is not (a false positive) and a Type II error is not believing a pattern is real when it is (a false negative). Imagine that you are a hominid on the planes of Africa and you hear a rustle in the grass. Is it a dangerous predator or just the wind? If you assume it is a dangerous predator and it is just the wind, you have made a Type I error, but to no harm. But if you believe the rustle in the grass is just the wind when it is a dangerous predator, there’s a good chance you’ll be lunch and thereby removed from your species’ gene pool. Thus, there would have been a natural selection for those hominids who tended to believe that all patterns are real and potentially dangerous. I call this process patternicity (the tendency to find meaningful patterns in random noise) and agenticity (the tendency to believe that the world is controlled by invisible intentional agents who may mean us harm). This, I believe, is the basis for the belief in souls, spirits, ghosts, gods, demons, angels, aliens, intelligent designers, government conspiracists, and all manner of invisible agents intending to harm us or help us.

People are religious because we are social and we need to get along. The moral sentiments in humans and moral principles in human groups evolved primarily through the force of natural selection operating on individuals and secondarily through the force of group selection operating on populations. The moral sense (the psychological feeling of doing “good” in the form of positive emotions such as righteousness and pride) evolved out of behaviors that were selected for because they were good either for the individual or for the group; an immoral sense (the psychological feeling of doing “bad” in the form of negative emotions such as guilt and shame) evolved out of behaviors that were selected for because they were bad either for the individual or for the group. While cultures may differ on what behaviors are defined as good or bad, the moral sense of feeling good or feeling bad about behavior X (whatever X may be) is an evolved human universal. The codification of moral principles out of the psychology of the moral sentiments evolved as a form of social control to insure the survival of individuals within groups and the survival of human groups themselves. Religion was the first social institution to canonize moral principles, and God as an explanatory pattern for the world took on new powers as the ultimate enforcer of the rules.

Thus it is that people are religious and believe in God.

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Souls, spirits, ghosts, gods, demons, angels, aliens, intelligent designers, government conspirators, and all manner of invisible agents with power and intention are believed to haunt our world and control our lives. Why?

The answer has two parts, starting with the concept of “patternicity,” which I defined in my December 2008 column as the human tendency to find meaningful patterns in meaningless noise. Consider the face on Mars, the Virgin Mary on a grilled-cheese sandwich, satanic messages in rock music. Of course, some patterns are real. Finding predictive patterns in changing weather, fruiting trees, migrating prey animals and hungry predators was central to the survival of Paleolithic hominids.

The problem is that we did not evolve a baloney-detection device in our brains to discriminate between true and false patterns. So we make two types of errors: a type I error, or false positive, is believing a pattern is real when it is not; a type II error, or false negative, is not believing a pattern is real when it is. If you believe that the rustle in the grass is a dangerous predator when it is just the wind (a type I error), you are more likely to survive than if you believe that the rustle in the grass is just the wind when it is a dangerous predator (a type II error). Because the cost of making a type I error is less than the cost of making a type II error and because there is no time for careful deliberation between patternicities in the split-second world of predator-prey interactions, natural selection would have favored those animals most likely to assume that all patterns are real.

But we do something other animals do not do. As large-brained hominids with a developed cortex and a theory of mind — the capacity to be aware of such mental states as desires and intentions in both ourselves and others — we infer agency behind the patterns we observe in a practice I call “agenticity”: the tendency to believe that the world is controlled by invisible intentional agents. We believe that these intentional agents control the world, sometimes invisibly from the top down (as opposed to bottom-up causal randomness). Together patternicity and agenticity form the cognitive basis of shamanism, paganism, animism, polytheism, monotheism, and all modes of Old and New Age spiritualisms.

Agenticity carries us far beyond the spirit world. The Intelligent Designer is said to be an invisible agent who created life from the top down. Aliens are often portrayed as powerful beings coming down from on high to warn us of our impending self-destruction. Conspiracy theories predictably include hidden agents at work behind the scenes, puppet-masters pulling political and economic strings as we dance to the tune of the Bilderbergers, the Rothschilds, the Rockefellers or the Illuminati. Even the belief that the government can impose top-down measures to rescue the economy is a form of agenticity, with President Barack Obama being touted as “the one” with almost messianic powers who will save us.

There is now substantial evidence from cognitive neuroscience that humans readily find patterns and impart agency to them, well documented in the new book SuperSense (HarperOne, 2009) by University of Bristol psychologist Bruce Hood. Examples: children believe that the sun can think and follows them around; because of such beliefs, they often add smiley faces on sketched suns. Adults typically refuse to wear a mass murderer’s sweater, believing that “evil” is a supernatural force that imparts its negative agency to the wearer (and, alternatively, that donning Mr. Rogers’s cardigan will make you a better person). A third of transplant patients believe that the donor’s personality is transplanted with the organ. Genital-shaped foods (bananas, oysters) are often believed to enhance sexual potency. Subjects watching geometric shapes with eye spots interacting on a computer screen conclude that they represent agents with moral intentions.

“Many highly educated and intelligent individuals experience a powerful sense that there are patterns, forces, energies and entities operating in the world,” Hood explains. “More important, such experiences are not substantiated by a body of reliable evidence, which is why they are supernatural and unscientific. The inclination or sense that they may be real is our supersense.”

We are natural-born supernaturalists.