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

by Steven Novella

Contained within the belief system of alchemy is the idea that a single sperm contains a miniature person—fully developed, merely scaled down to sperm size.

For reflexologists, the foot is the “little man” of the body. For iridologists, the eye is the little man. For palmists, the little man is the palm.

There is no underlying anatomy or physiology that can explain how the iris, the foot, or the palm could reflect the state of function of any other part of the body.

Homunculus theory is mainly a desire for simplicity, to subsume all the complexities of biology in one nice neat little system.

Furthermore, there are real homunculi in your brain. For example, there is a motor homunculus, a motor strip in your cortex that actually does map to your body. These are real connections. Those brain cells give off axons that actually go to all parts of the body through the spinal cord and nerves. Developmentally, this is called somatotopic mapping. When the brain is forming, it maps itself to neurons connecting to other parts of the body, along both the motor and sensory strip. This also works for the retina, which maps to the visual cortex. We can see the brain’s homunculi when we map the brain’s function, and we can follow their connections to the body.

And even chiropractic—straight chiropractic, specifically—postulates that the spinal cord and the vertebrae map to different organs in your body, even when those nerves don’t actually go to or provide any kind of nerve supply to those organs.

That, however, didn’t stop the 2010 Jerusalem International Conference on Integrative Medicine from accepting an abstract based on a newly invented homunculus system. The abstract was submitted by Dr. John McLachlan, who later published the results of his prank in the BMJ. He presented case reports and testimonials, which, he claimed, established the usefulness of “butt reflexology.” That’s right, he just superimposed the real homunculi from the brain onto a schematic of human buttocks and invented a new “alternative” medical system. His abstract was gleefully accepted for presentation at the conference.

And be suspicious of ancient prescientific ideas. They really had no clue, so unless their ideas have been reasonably demonstrated and explained by modern science, they probably are as nonsensical as they sound.

35. Skeptics’ Guide Entry: Intelligent Design

Section: Cautionary Tales

See also: Creationism, Fun...

Intelligent design (ID) is the notion that the complexity of the universe can only be explained as the result of ...

Design in nature is but a concatenation of accidents, culled by natural selection until the result is so beautiful or effective as to seem a miracle of purpose. —Michael Pollan

The core belief of ID, according to the Discovery Institute (the main organization promoting this idea), is as follows: Intelligent design holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection.

ID lacks the minimal criterion to be considered science: falsifiability.

ID proponents, of course, reject this argument, because the entire purpose of ID is to disguise creationism as a scientific theory.

They desperately want ID to be considered legitimate science—that is in fact the entire reason for its existence. But they cannot allow for it to be actually falsified by scientific data, for that again would defeat the purpose.

This is the game: pretending ID can be falsified, but then always keeping it just out of reach of scientific evidence so that in practice it can never be falsified.

Asking the Wrong Question

The question is not whether or not there is design in nature, but what the nature of that design is. Evolution is a bottom-up process whereby design and complexity emerge out of blind but nonrandom processes. “Intelligent” design, by contrast, is a top-down process where the final result is known ahead of time by the designer and is achieved with purpose.

If we ask the correct question—does life display bottom-up or top-down design?—the answer is obvious to anyone with sufficient knowledge of biology and an unbiased mind. Life is overwhelmed by the features of bottom-up design, from the vestigial eyes of cave salamanders to the bits of viral DNA junking up our genome.

Common Descent

The “God can make life to look like whatever he wants” defense renders the beliefs of anyone who makes it unfalsifiable.

Irreducible Complexity

The premise is that if a structure could not function for its current purpose if it were any simpler (if any complexity were removed), then such a structure couldn’t have evolved because it couldn’t have passed through simpler forms to get to its irreducibly complex state, because evolution requires that in order to be selected, a structure would have to provide an adaptive advantage every step of the way.

Specifically, the premise ignores the possibility that an irreducibly complex structure could have evolved from a simpler structure that served a different purpose.

The premise is also false because natural selection isn’t the only force operating in evolution. There is also genetic drift, which is random variation not under selective pressures.

In practice the notion of irreducible complexity contains two strategies. The first is to argue that a biological entity could not be simpler even in theory, which we’ve proven invalid. So ID proponents fall back to their second strategy, arguing that evolutionists haven’t fleshed out the actual evolutionary history of an apparently irreducibly complex structure or pathway.

What has happened since Behe made his initial claims for irreducible complexity is that scientific progress has continued and many of the holes in current knowledge that Behe relied upon have been filled in, like the bacterial flagellum example above.

What they’re admitting, without meaning to, is that ID is ultimately a “god of the gaps” belief, and the only way to falsify it is to close every single last gap.

The False Dichotomy

What they won’t do is make any statements about the intelligent designer. What marks would such an intelligence leave upon creation? No one appears to know. When pressed, they often play the “it’s a mystery” card. How can we possibly fathom the intelligence necessary to design and create life? Evolution, on the other hand, does make many specific predictions about what evolved life should look like—predictions that have been validated. Evolution’s successful positive predictions are a problem for ID, but they deal with them by arguing that the designer could have arbitrarily and inexplicably decided to make life look as if it evolved.

Since the intelligent designer (by which, let’s face it, they mean God) can, according to ID proponents, create life to look like anything, no possible observation of life can falsify such a designer.

The challenge that remains open for the ID community is to state a specific prediction about what positive evidence should be present if life were top-down intelligently designed. They cannot do this.

Intelligent design holds that certain features of the universe and of living things were caused by an intelligent agent who, for reasons we do not care to get into, chose to make the world look exactly as if it were the product of random variation and natural selection.

36. Skeptics’ Guide Entry: Vitalism and Dualism

Section: Cautionary Tales

See also: Life Force...

Vitalism is the belief that living things are animated by a life force, or “vital” force, that gives them not only the quality of being alive but also their essence. Dualism is the same concept applied to consciousness—tha...

Science does not aim at establishing immutable truths and eternal dogmas; its aim is to approach the truth by successive approximations, without claiming that at any stage final and com...

Our brains are in fact organized to divide the world into these two categories—the animate (which it operationally defines as moving in a way that suggests agency) and inanimate. Our brains assign direct emotional significance to animate things but not to inanimate things.

Vitalism became worse than wrong—it was simply unnecessary. It stands as an excellent historical example of how ideas emerge and fade in science, and how important it is to recognize when a scientific notion is supported by evidence and when it is just a guess we use to explain the unknown.

In a 2013 study looking at vitalistic thinking in adults, researcher Stuart Wilson found that belief in a vital force corresponded strongly with beliefs in the paranormal and New Age philosophy.

Chiropractic (at least the purist form, still practiced by about 30 percent of chiropractors) is based upon so-called “innate intelligence,” which is their term for the life force. D. D. Palmer, who made up chiropractic, claimed that innate intelligence would descend from heaven into your brain and then down through the spinal cord to the rest of the body. Subtle subluxations, or misalignments of the spine, cause health problems because they are blocking the flow of innate. I have never heard an explanation for how someone with a spinal cord injury can live at all with such a complete blockage of their innate.

Another life energy–based treatment is therapeutic touch, which consists of waving the hands over a person, fluffing up and unblocking their “human energy field.”

Reiki is essentially the same thing, just using t...

Traditionally, acupuncture is explained as placing needles into special points that represent critical junctures in the flow of chi, unbl...

Despite its continued popularity, the vital life force remains a prescientific placeholder displaced by our knowledge of biology.

Susan Blackmore said: When I say that consciousness is an illusion I do not mean that consciousness does not exist. I mean that consciousness is not what it appears to be. If it seems to be a continuous stream of rich and detailed experiences, happening one after the other to a conscious person, this is the illusion.

It has now been established beyond any scientific doubt that the mind is what the brain does. The functioning of the brain is consciousness. In a sense, we are our brains.