Misstatements and Dubious Claims of Carl Sagan

Carl Sagan was a scientist who enjoyed great influence in the 1970's and 1980's.  In books, a weekly column and a television show (the original version of the Cosmos series), Sagan advanced rather dogmatically a set of ideas that were widely influential. His ideas are summarized in the visual below depicting stone tablets:

Reality according to Carl Sagan

When I was a young man in my early twenties, Carl Sagan was at the height of his influence, and I bought quite a few of these ideas. But now quite a few of these ideas seem dubious or untenable. As a whole, the Sagan Creed lacks coherence, and parts of it seem to contradict other parts of it. For example, if it were true that the galaxy was teeming with so many extraterrestrial civilizations, why should we not expect that some of them are visiting us now, or have visited us in the past? And if mere chance is behind the origin of life, why should it be that extraterrestrial life should be common? Given the immense improbability of life appearing by chance from lifeless chemicals, it would seem that if mere chance is controlling things, that extraterrestrial life should be very rare or nonexistent. And if there are extraterrestrial civilizations millions of years older than us, why should we think that we would be able to communicate with them using radio? You would think such godlike entities would have some far more sophisticated means of communication. 

Let us look at an interview Carl Sagan gave to the magazine Rolling Stone in 1980, at the height of his influence. Defending the theory of evolution by natural selection in his interview, Sagan provides no evidence that anything has actually been produced by such a process. He merely states, “It’s hard to see how evolution by natural selection wouldn’t work.” To the contrary, anyone examining the unfathomable complexity and information richness of biological organisms should have the strongest reason for doubting that what Sagan mentions should work to produce such wonders. Random mutations can be accurately and concisely described as noise. Darwinian evolution by natural selection can be concisely described as the theory that noise sometimes get incredibly lucky, and that such noise luckily piles up to become incredibly organized systems more functionally intricate than anything humans have created (as well as vast libraries of functional information). It is anything but clear that such a thing could possibly work. People who have good evidence that something works show us the evidence that the thing works. They do not make statements such as “It's hard to see how it would not work.”

Rather suspiciously, while defending Darwinism, Sagan makes an appeal to the claim that we should not rely on common sense. He refers to the “inapplicability of common sense.” He then states the following:

“It is true that natural selection as the cause of evolution is a hypothesis. There are other possibilities.”

This does not seem like the ringing endorsement that we might expect if the case for such a cause was very strong.

In the interview Sagan tries to drum up some “the universe helped produce us” enthusiasm by making some very dubious claims. He states this:

“Cosmic rays that are produced in the death throes of stars are partly responsible for the mutations that have led to us—the changes in the genetic material. The origin of life was spurred by ultraviolet light from the sun and lightning, which in turn is caused by the heating of the earth by the sun.”

Mutations are noise. The idea that mutations of any type caused the incredibly fine-tuned proteins in humans is no more logical than the idea of typing monkeys producing technical instruction manuals. Since genomes do not actually specify phenotypes,  since DNA is not a blueprint or a recipe for making either human beings or any part of a human being larger than a protein molecule, and since there is no proof or good evidence that any single protein molecule arose from random mutations, it is not a statement of fact to refer to “the mutations that have led to us,” but merely a repetition of a dubious article of faith. 

Sagan frequently spoke and wrote on the topic of the origin of life, but seemed to never deal with it candidly or honestly by discussing the fantastically intricate fine-tuned arrrangements of matter needed to get life started.  His "just add energy" idea that so gigantically improbable an arrangement of matter was “spurred by ultraviolet light from the sun and lightning” was goofy talk, like saying that a lightning storm or wind storm could cause the scattered pebbles on a beach to assemble into a long meaningful message. 

Later in the interview Sagan then makes this ludicrous statement:

“We are naturally scientists. It’s the only thing we do substantially better than other creatures.”

Of course, this is nonsense. There are 1001 things that humans do substantially better than other creatures, such as art, philosophy, film-making, education and computer programming.

In episode 2 of the original Cosmos series, Sagan discussed the origin and history of life, using "we've got this figured out" kind of language that was very inappropriate given the subject matter.  Below are some of the weak points in his discussion:

• After discussing a primordial soup, he claimed that “one day, quite by accident a molecule arose that was able to make crude copies of itself using as building blocks the other molecules in the soup,” failing to tell us that no such self-reproducing molecule has ever been produced under experimental conditions simulating the early Earth, and that not even any  building blocks of such a molecule (nucleosides) have been produced in experiments simulating the early Earth.
• He explained the origin of the first cell by merely mentioning molecules and by stating “varieties with specialized functions joined together making a collective...the first cell,” failing to mention that a self-reproducing cell would require about 300 different types of such molecules “with specialized functions” (300 different types of protein molecules), that every one of these different types would be as complex (and as unlikely to form by chance) as a well-functioning 100-word computer program, and that there is not the slightest reason why such molecules “with specialized functions” (needed by a cell) would happen to exist prior to the existence of the first cell, making this “joining together” a miracle of luck if it occurred by chance.
• He completely ignores the problem of explaining eukaryotic cells, which are not explained by anything he discussed.
• He handles the mountainous problem of explaining the appearance of multicellular organisms merely through the not-very-helpful explanation that one-celled organisms "joined together," which sounded as vacuous as the "stuff joined together" explanation he gave to explain the appearance of the first cell. 
• He states, "Then, suddenly...there was an enormous proliferation of new life forms, an event called the Cambrian Explosion," without doing anything to explain how that could occur, and without noting how such an event is inexplicable using only the gradualist explanations he has previously given. 

In episode 2 of the original Cosmos series, Carl Sagan stated the following utterly fallacious logic (which was repeated by Neil de Grasse Tyson in the second Cosmos series): 

"But if artificial selection makes such changes in only a few thousand years what must natural selection working for billions of years, be capable of? The answer is all the beauty and diversity in the biological world."

Read more: https://www.springfieldspringfield.co.uk/view_episode_scripts.php?tv-show=cosmos-carl-sagan&episode=s01e02

This statement commits a logic error. It would be logically correct to make a statement like this:

"If wind erosion can produce a 1% deformation in something in 10 years, how much of a deformation might wind erosion produce in 500 years? Easily 20% or more."

But by asking us to draw a conclusion about the power of natural selection (something blind and unguided) from the power of artificial selection (something guided by human choices), Sagan committed a logic error as bad as the logic error in the statement below:

"If non-blind painters can paint 100 landscape masterpieces in 200 years, how many landscape masterpieces might blind painters have painted in 500 years? Easily hundreds."

In episode 11 of the original Cosmos TV series, Sagan spoke as if scientists knew how a brain could store memories, claiming that every brain connection represents one bit of information: "What we know is encoded in cells called neurons...every connection representing one bit of information." In neither his time nor our time does any scientist have a detailed credible theory as to how a brain could either encode or store human episodic and conceptual information by any physical means, and there is zero evidence that  human memories are stored or encoded as digital information involving bits. Any theory of a digital storage of human memories in the brain is ruled out by the short lifetimes of the protein molecules in brains, which last for only weeks. Talking on and on about the brain, Sagan presented no actual evidence of having any understanding of how a brain could perform any of the higher mental human capabilities,  other than the vague idea that thought comes from the frontal cortex, an idea discredited here. 

Stating very dogmatically an element of the Sagan Creed listed above, Sagan began episode 12 of the original Cosmos TV series by stating,  "In the vastness of the cosmos there must be other civilizations far older and more advanced than ours."  It is certainly not true that there "must be" such extraterrestrial civilizations, for a variety of reasons. The first is the vast mathematical improbability of life ever arising from chemicals by mere chance processes.  The second is the almost equally vast improbability of life ever reaching a state of multicellular organization and intelligence by chance processes. The third reason is the very significant chance that any civilization arising would not last for more than a few centuries or millenia after it achieved atomic power.  Sagan stated, "Extraordinary claims require extraordinary evidence," but did not apply such a principle to prevent himself from making extraordinary claims about the existence of civilizations far more advanced than ours, claims not supported by any evidence. 

At about the 1:09 minute mark in the interview here,  Sagan claimed to understand the nature of humanity's status in the galaxy. He stated, “If you look at time scales, you realize that our civilization is the most backward civilization in the galaxy that can communicate.” Of course, we know nothing of the sort. If life is common in the galaxy, there could easily be many other communicating civilizations that are more backward than our own. 

At about the 2:15 mark in the interview Sagan began to tell a great big falsehood related to extraterrestrial life.  He stated the following:

"The carbon-rich complex molecules that are essential for the kind of life we know about, are fantastically abundant. They litter the universe. We see them in asteroids, and comets, and the moons and the outer solar system, and even in the cool dark spaces between the stars. So the stuff of life is everywhere."

He thereby led his listeners to think that “stuff of life” has been discovered in outer space. No such thing has occurred. The “stuff of life” would be things such as nucleic acids and proteins, and they have never been discovered in outer space. There are virtually no signs of the building blocks of life in outer space. None of the twenty amino acids used by living things has been discovered in space, other than the simplest amino acid, glycine (which was not found in space while Sagan lived). Sagan frequently repeated this "stuff of life is everywhere" falsehood in a variety of places. 

In an interview on January 1, 1995, Sagan suggested that planet Earth is very insignificant, partially on the grounds that  "this universe is one of an enormous number, maybe even an infinite number, of other closed off universes," a claim for which there is no evidence whatsoever.  But so it was in Sagan-speak: facts all mixed up with speculation, and the strange mixture sold as "science." In the same interview, Sagan sunk into pure nonsense talk by claiming that "all of our vaunted uniqueness turns out to be shared with other animals," a statement that can be very quickly disproved by referrring to the simple fact that only humans speak and do philosophy and write books and have abstract ideas. 

Quite misleadingly in this 1995 interview, astronomer Sagan says nothing about the evidence that the universe is only 13 billion years old, and seems to suggest that the universe has existed forever. He states this:

"We expect the universe to go on forever into the future. Why do we have the idea that it doesn't go on forever into the past?"

The answer to this question was well-known to every professional astronomer in 1995: that the expansion of the universe (known by the redshift of galaxies) and the cosmic background radiation tell us that the universe had a unique sudden origin about 13 billion years ago.  

One of Sagan's last writings was The Demon Haunted World: Science as a Candle in the Dark, a book on the topic of paranormal phenomena.  The long book shows quite a bit of erudtion and has quite a few scholarly flourishes, but the erudition is mainly concerning extraneous or tangential topics. Sagan showed zero signs of having seriously researched any of the better evidence for paranormal phenomena.  He shows no sign of having read any of the 40 most important books he should have read before writing on such a topic. 

On page 259 of that book, Sagan repeated what I call the Great DNA Myth, the hugely misleading and utterly erroneous claim that DNA is a specification for making a human being.  He stated, "Molecular biologists are busily recording the sequence of the three billion nucleotides that specify how to make a human being." That job was finished in the year 2003 when the Human Genome Project was completed, and no such specification of "how to make a human being" was ever found in DNA or its nucleotide sequences. When Sagan wrote the words, we already knew why DNA could not possibly be a specification of "how to make a human being," because we knew that DNA only specifies low-level chemical information such as the amino acid sequences of proteins, not higher-level structural information such as how to make a cell or an organ or organ system or a human.

A DNA molecule bears not the slightest resemblance to either a blueprint for making a human being, or a set a instructions (a recipe or program) for making a human being.  DNA does not specify how to make any full organism. DNA does not specify how to make any organ system or appendage of any organism. DNA does not specify how to make any organ of any organism. DNA does not even specify how to make any of the 200 types of cells used by humans. But in episode 11 of the original Cosmos TV series,  Carl Sagan made the very fictional claim that DNA is "a complete library of instructions of how to make every part of you." 

Telling a human that he originated because some DNA blueprint was read (when nothing like such a DNA blueprint has ever existed in any human) is a falsehood far more serious than, say, telling a young boy that his father is not the doctor he lives with, but some unknown truck driver.  Both are gigantic falsehoods regarding a person's origin, and the first of these is far more serious a lie. Misidentifying someone's father is at least in the right ballpark (both the doctor and truck driver being humans). When a person believes that he arose because of the reading of a DNA body blueprint (something that has never existed in any human), he will get an idea about his origin that is not at all in the right ballpark; and as a result he may get a "a human is just chemistry" idea that is both false and morally corrosive. 

Apparently not ever having bothered to seriously study any of the massive evidence for paranormal psychic phenomena inexplicable by brain activity, nor having bothered to study any of the massive neuroscience evidence suggesting that the mind and memory cannot be explained by the brain (such as the fact that people with half brains or quarter brains can think and remember very well), Sagan made the claim that there is "not a shred of evidence" for the idea that the mind is more than the brain. This was a misstatement as false as his mythical claim about DNA being a specification of "how to make a human being," and his mythical claim about a "genetic language in which is written the diverse skills and propensities of every being on Earth." Genes (merely small parts of DNA) do not specify how to make a human being, and do not explain any mind skills such as imagination or creativity or abstract reasoning or instant memory recall or moral reasoning. Given the genetic code that limits genes to stating very low-level chemical information such as the amino acid sequences in proteins, it is utterly impossible that a gene could "write a skill" such as how to compose music or how to reason mathematically or how to think philosophically. Sagan promoted the erroneous idea that the brain is "programmed,"  referring to "how cleverly the brain is packaged and programmed." Nothing like software or programming has ever been discovered in a brain. 

Faced with massive reports of near-death experiences, Sagan advanced the silly idea that such things are rememberances of the experience of birth. He suggested that reports of passing through a tunnel toward a bright light are memories of passing through a birth canal and moving towards the light of a hospital.  This idea made no sense for two reasons: (1) people don't remember anything that happened in the first year of their lives; (2) when a baby tightly squeezes through a vaginal birth canal, its eyes are not pointing towards the exit of such a canal; so a being-born baby doesn't actually have a visual experience similar to a near-death experience. 

Although he did good work on some tasks such as alerting people to the dangers of nuclear arsenals, and usually had his heart in the right place, Carl Sagan was someone who pretended to know many things he did not actually know. He stated many of his unproven or dubious dogmas or speculations with such smug assurance that it helped fool many people into thinking that scientists know much more than they do know. And like quite a few of today's professors, Sagan sometimes played fast and loose with the facts to help prop up the speculations or dogmas he was trying to sell. Scientists have done the search for extraterrestrial radio signals that Sagan lobbied for in the 1970's, but they have come up empty-handed, suggesting that Sagan was way off in his estimations of how many civilizations existed in our galaxy.  

Sagan's 13-part Cosmos series was the very model of crowing scientist overconfidence. It would be great if one day someone did a 13-part television series serving as a corrective to such pretentious braggadocio. It might be a series discussing all of the very great limitations of modern knowledge, all of the conflicting signals nature sends us, and all of the many reasons for doubting the dogmatic claims taught by professors pushing their belief systems.  A good title for such a series might be What We Don't Know. 

Postscript: An examination of the book Intelligent Life in the Universe by Carl Sagan and I. S. Shklovskii will reveals some additional glaring misstatements. For example, on page 9 the authors make this hugely untrue statement: "It is now apparent that the origin of life can be explained, to a large extent, by studies in the field of chemistry." No such studies had occurred when that statement was written, and no such studies have ever occurred. On page 253 of his book Billions and Billions, Sagan told us this gigantically grotesque lying boast about DNA:  "The most significant aspect of the DNA story is that the fundamental processes of life now seem fully understandable in terms of physics and chemistry." To the contrary, scientists lack any credible explanation of so simple a thing as how human cells are able to reproduce; they lack any credible explanation of the most basic mental processes such as thinking and memory; and since DNA is not a specification for making a human, scientists lack any credible explanation for the progression from a speck-sized zygote to an adult human.