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

by Steven Novella

There is no evidence of any consciousness without brain function or after death.

If you look at the hypothesis that the brain causes consciousness, and then you make predictions based on that hypothesis, it turns out every one of those predictions is true. To deny this connection is to deny all of modern neuroscience. In that way modern dualists are neuroscience deniers in the same exact way that creationists are evolution deniers.

They deny the current model of biological neuroscience in order to manufacture a gap, and then they try to slip their dualism—their “ghost in the machine”—into it.

Mind of t...

“So far, what our cognitive science has found out about the mind is mostly that we don’t know how it works.”

Science progresses largely by creating a more and more detailed picture of nature, digging deeper and deeper into how the world works. Generally, lower-level or more detailed questions don’t affect higher-level ones. Even if they reveal an anomaly that cannot be explained by the overall paradigm, this usually results in a modification of the paradigm, not a dismissal of it.

We have also identified many of the components of consciousness, localized them to specific brain regions. For example, we’ve pinpointed brain regions that create the sense we are inside our bodies, that we exist as an entity separate from the rest of the universe, and that allow us to direct our attention and form memories. We long ago determined those parts of the brain that see, feel, plan and execute movement, and generate emotional reactions. With functional MRI studies neuroscience has accelerated, and we are quickly reverse engineering the brain piece by piece.

Scientists follow what works.

Neuroscience works as an explanation of mind and consciousness, and we no longer have to invoke a spirit to fill in the gaps.

Cartesian Dualists

Here’s what they say: Physical things have a location. You can say where your house is. They have size, mass, and shape—the properties of material things. Then the dualists ask, “What is the size of an emotion, the shape of a memory, or the mass of your dreams?” Consciousness, they argue, doesn’t have the properties of material things, therefore it is not a material thing. Therefore it is something else. Let’s call it spiritual. This may sound superficially interesting, but it is utter nonsense. They are making what we call a category mistake. They are assuming that consciousness is a thing, and they’re wrong. The brain is a thing, and it has all the properties of a thing. The mind is not a thing, it is a process. The mind is not the brain, it is what the brain does—it is the brain in action.

Light Fairies

Another way that dualists attempt to rescue their belief from the avalanche of neuroscientific evidence is to appeal to the “correlation is not necessarily causation” fallacy. They say, “Sure, the brain correlates with the mind in all those ways you point out. But that doesn’t mean the brain causes the mind.” Perhaps, they argue, the brain is simply a receiver for the mind, which lies outside of the physical. If you change the channel on your TV (the TV being the brain in this analogy), that changes the program, but the TV didn’t cause the program. This analogy fails, however. I might be able to change the channel, but I cannot change what the actors do on a television show by adjusting the TV. I cannot turn a drama into a comedy.

The Hard Problem

We don’t yet know all the elements of brain function that are essential for consciousness or know how they work together, but we are making steady progress.

The brain’s committee seems to be a bit chaotic, with everyone shouting for attention and talking over one another. They may even fight, but in the end a collective decision is made.

Chalmers isn’t a Cartesian dualist, he’s a property dualist. He feels that consciousness is a manifestation of the material world, just a phenomenon currently unknown to science. Chalmers talks about what he calls philosophical zombies (or “p-zombies” for short). He argues that it’s possible to imagine a being that does everything a human does but is not aware of its own experience. Subjective experiences of things, such as the experience of seeing red, are called qualia. So, Chalmers asks, why are there qualia?

The other side of this argument is perhaps best articulated by Daniel Dennett. He says, essentially, that there is no hard problem. It’s easy problems all the way down. Once you have solved all the easy problems, then you’ve solved the hard problem by extension. To explain further, he encourages you to simply ask, “And then what happens?” The brain sees an image; that information goes to the association cortex, which gives it meaning as a thing; and then that information goes to the amygdala for the assignment of emotion to the thing you are seeing (if it is living). And then what? Well, then that information goes to some other part of the brain where memories are stored. And then what? Well, that provokes a pattern recognition in your memory of a previous event involving the object. And then what? Then that information goes again to the emotional centers to provoke the emotions you have associated with that memory. And the chain keeps going. It never stops. All these components of brain function that we’ve identified just keep going around in circles. The brain talks to itself, it receives new information, it activates circuits and networks, which provokes other networks, on and on until you die. That endless chain of activity (which pauses when you sleep but is actually replaced by other types of brain activity that just don’t produce wakefulness) is your stream of consciousness. It doesn’t ever have to go anywhere or report to anything. It’s simply consciousness. Theref...

It is quite possible that, because our brains evolved to give us the very useful illusion of a continuous stream of seamless consciousness, we evolved to not easily grasp our own consciousness. That would require piercing the illusion.

37. Skeptics’ Guide Entry: N-Rays

Section: Cautionary Tales

See also: Pseud...

The story of N-rays is a classic tale of how bias can affect research, how an appealing fad can take hold, and how a little bit of...

The scientific method consists of the use of procedures designed to show not that our predictions and hypotheses are right, but that they might be wrong. Scientific reasoning is useful to anyone in any job because it makes us face the possibi...

Between 1903 and 1906 no less than three hundred papers on N-rays were published in the scientific literature, involving about a hundred scientists and medical researchers. At least forty scientists claimed to see these N-rays.

The science of N-rays was taking off, but there was one slight problem. N-rays do not exist. All of this research was nothing more than self-deception.

Scientific reputations and French pride were on the line. The French physics community would certainly have wanted their own electromagnetic radiation to match the Germans’ X-rays, so it was easy for them to tell themselves that the German and English researchers just weren’t doing it right: They didn’t have the sensitive eye necessary to see the subtle glow of the thread that was the only evidence N-rays existed.

To settle this growing dispute, Robert W. Wood of Johns Hopkins University was sent by the journal Nature to observe Blondlot’s experimental procedure.

As he later wrote: “I went, I must confess, in a doubting frame of mind, but with the hope that I might be convinced of the reality of the phenomena, the accounts of which have been read with so much scepticism.”

He had a reputation for being a prankster. He was also a science popularizer and took it upon himself to investigate and debunk the pseudoscience of his day.

Wood spent hours in Blondlot’s lab conducting several experiments to see if the N-rays could be reliably demonstrated.

The presence of his hand in the pathway of the N-rays should have been enough to block them, so, in the darkened room, he asked his colleagues to view the thread and tell him when his hand was blocking the N-rays. They couldn’t reliably do so, stating that the thread was dimming or brightening even when his hand was still.

Finally, Wood performed the control for which he is most famous. In the third experimental setup, an aluminum prism was used to bend the N-rays and spread them out into a spectrum. As he recounted in his eventual letter to Nature detailing his observations:

I was unable to see any change whatever in the brilliancy of the phosphorescent line as I moved it along, and I subsequently found that the removal of the prism (we were in a dark room) did not seem to interfere in any way with the location of the maxima and minima in the deviated (!) ray bundle. I then suggested that an attempt be made to determine by means of the phosphorescent screen whether I had placed the prism with its refracting edge to the right or the left, but neither the experimenter nor his assistant determined the position correctly in a single case (three trials were made). This failure was attributed to fatigue.

Lessons from N-rays

In science it pays to be one’s own most vehement critic and greatest skeptic. This means trying earnestly to prove your own hypothesis wrong, and tentatively accepting it only to the degree that it survives dedicated attempts at doing so.

History Repeats Itself

In 1988 Benveniste published a paper in Nature magazine claiming that water retains the memory of substances that had been diluted in it—even through extreme dilutions.

Benveniste’s claim was that even when the original substance is gone, the water retains its chemical signature through its own structure.

He claimed that water that once had antibodies in it could still activate basophils after the antibodies were diluted away.

John Maddox, then editor of Nature, published the results even though he was skeptical of their validity, because the paper had survived peer review. But, in keeping with the history of his prestigious journal, he went to inspect the experimental procedure for himself. He took along Walter Stewart of the National Institutes of Health, who was an investigator of scientific fraud, and noted skeptic and magician James Randi. Like Wood before them, they published their findings in a follow-up article in Nature, detailing a number of failings of Benveniste’s lab.

When properly blinded, the replicated experiments were negative. The only debate among the investigators was whether the original results were due to bias or fraud. It was noted that one co-researcher critical to carrying out the experiments, Elisabeth Davenas, was the only one who could consistently produce positive results.

Like Blondlot, Benveniste ignored multiple anomalies in the data that should have prompted skepticism. He further refused to adhere to the blinded results, instead dismissing the investigation as a “witch hunt.”

Humans in general are great at coming up with reasons to maintain their desired beliefs in the face of contradictory data. More intelligent and educated people aren’t necessarily better at critical thinking, but they are likely to be more clever and creative in coming up with such excuses—and scientists are no exception.

38. Skeptics’ Guide Entry: Positive Thinking