Monthly Archives: April 2025

Carl Sagan’s ‘Baloney Detection Kit’

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Carl Sagan, in The Demon-Haunted World, presents a set of tools for sceptical thinking that he calls the “baloney detection kit”. Sceptical thinking consists both of constructing a reasoned argument and recognizing a fallacious or fraudulent one. In order to identify a fallacious argument, Sagan suggests employing such tools as independent confirmation of facts, debate, development of different hypotheses, quantification, the use of Occam’s razor, and the possibility of falsification. Sagan’s “baloney detection kit” also provides tools for detecting “the most common fallacies of logic and rhetoric”, such as argument from authority and statistics of small numbers. Through these tools, Sagan argues the benefits of a critical mind and the self-correcting nature of science can take place.

Sagan provides nine tools as the first part of this kit.

  1. There must be independent confirmation of the facts given when possible.
  2. Encourage debate on the evidence from all points of view.
  3. Realize that an argument from authority is not always reliable. Sagan supports this by telling us that “authorities” have made mistakes in the past and they will again in the future.
  4. Consider more than one hypothesis. Sagan adds to this by telling us that we must think of the argument from all angles and think all the ways it can be explained or disproved. The hypothesis that then still hasn’t been disproved has a much higher chance of being correct.
  5. Try to avoid clinging obdurately to your own hypothesis and so become biased. Sagan tells us to compare our own hypothesis with others to see if we can find reasons to reject our own hypothesis.
  6. Quantify. Sagan tells us that if whatever we are trying to explain has numerical value or quantitative data related to it, then we’ll be much more able to compete against other hypotheses.
  7. If there is a chain of argument, every link in that chain must be correct.
  8. The use of Occam’s razor, which says to choose the hypothesis that is simpler and requires the fewest assumptions.
  9. Ask if a given hypothesis can be falsified. Sagan tells us that if a hypothesis cannot be tested or falsified then it is not worth considering.

Sagan suggests that with the use of this “baloney detection kit” it is easier to critically think and find the truth

Logical fallacies

There is a second part to the kit. This consists of twenty logical fallacies that one must not commit when offering up a new claim.

  1. Ad hominem. An arguer attacks the opposing arguer and not the actual argument.
  2. Argument from authority. Someone expects another to immediately believe that a person of authority or higher knowledge is correct.
  3. Argument from adverse consequences. Someone says that something must be done a certain way or else there will be adverse consequences.
  4. Appeal to ignorance. One argues a claim in that whatever has not been proved false must be true, and vice versa.
  5. Special pleading. An arguer responds to a deeply complex or rhetorical question or statement by, usually, saying “oh you don’t understand how so and so works.”
  6. Begging the question. An arguer assumes the answer and makes a claim such as, this happened because of that, or, this needs to happen in order for that to happen.
  7. Observational selection. Someone talks about how great something is by explaining all of the positive aspects of it while purposely not mentioning any of the negative aspects.
  8. Statistics of small numbers. Someone argues something by giving the statistics in small numbers, which isn’t very reliable.
  9. Misunderstanding of the nature of statistics. Someone misinterprets statistics given to them.
  10. Fallacy of inconsistency. An arguer is very inconsistent in their claims.
  11. Non sequitur. This is Latin for “it doesn’t follow”. A claim is made that doesn’t make much sense, such as “Our nation will prevail because God is great.”
  12. Post hoc ergo propter hoc. Latin for “it happened after, so it was caused by”. An arguer claims that something happened because of a past event when really it probably didn’t.
  13. Meaningless question. Someone asks a question that has no real meaning or doesn’t add to the argument at all.
  14. The excluded middle. An arguer only considers or mentions the two opposite extremes of the conversation and excludes the aspects in between the two extremes.
  15. Short-term vs. long-term. A subset of the excluded middle, but so important it was pulled it out for special attention.
  16. Slippery slope, related to excluded middle (e.g., If we allow abortion in the first weeks of pregnancy, it will be impossible to prevent the killing of a full-term infant. Or, conversely: If the state prohibits…).
  17. Confusion of correlation and causation. The latter causes the former.
  18. Straw man. Caricaturing a position to make it easier to attack. This is also a short-term/long-term fallacy.
  19. Suppressed evidence, or half-truth.
  20. Weasel word. Talleyrand said: “An important art of politicians is to find new names for institutions which under old names have become odious to the public.” 

Sagan provides a skeptical analysis of several examples of what he refers to as superstition, fraud, and pseudoscience such as witches, UFOs, ESP,  faith healing and organised religion.

An alternative to The Demon-Haunted World is the equally accessible Nonsense on Stilts: How to Tell Science from Bunk, by Massimo Pigliucci (2008). One reviewer sums it it up well:

“No one—not the public intellectuals in the culture wars between defenders and detractors of science nor the believers of pseudoscience themselves—is spared Pigliucci’s incisive analysis. In the end, Nonsense on Stilts is a timely reminder of the need to maintain a line between expertise and assumption. Broad in scope and implication, it is also ultimately a captivating guide for the intelligent citizen who wishes to make up her own mind while navigating the perilous debates that will affect the future of our planet.”

Reading and absorbing these two books is possibly the best bit of education you can deliver to yourself. It is sad, but no accident methinks, that every child leaving school is not imbued with this understanding.

Carl Sagan – possibly the greatest influence on my understanding of this world and its place in the universe.

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Yesterday (18/04/25), a new article was published that focussed on the last ever television interview of Carl Sagan, back in 1996.

I am always heartened to see anything that brings attention to this great man, given that he has been gone approaching 30 years now. It dawned on me yesterday that he died at the same age that I am now, and this has given me further reason to reflect on the influence that he had on me in my formative years. More on this shortly.

But first, let us look at this article on the Open Culture website yesterday.

It has the link to the interview video at the top:

The Open Culture Foundation is a nonpartisan, nonprofit organisation founded in 2014 to promote open technology as the core to securing digital rights and internet freedom. “Open technology” includes three dimensions: (1) open source software & hardware that can freely used, developed and redistributed by anyone; (2) open data that can similarly be freely used, reused and redistributed by anyone; and (3) open government that promotes transparent, participatory, inclusive and accountable governance.

Hopefully you can see why Carl Sagan’s interview (and work) resonates with them so much. Sagan was a pioneering scientist, focussing on astronomy and astro-physics during the immensely progressive period of scientific advance during and beyond the 1960s; the era of the Apollo missions to the moon and deep-space probes. In this interview and in his seminal, sadly final book, The Demon-Haunted World, he identifies a problem that continues to grow and blight the futures of us all; namely people losing respect and understanding for science and scientists.

At the end of his life, Sagan cared deeply about where science stood in the public imagination. Sagan sensed that scientific thinking was losing ground in America, and especially worryingly in Congress. During his final interview, aired on May 27, 1996, Sagan issued a strong warning:

We’ve arranged a society on science and technology in which nobody understands anything about science and technology, and this combustible mixture of ignorance and power sooner or later is going to blow up in our faces. I mean, who is running the science and technology in a democracy if the people don’t know anything about it.

And he also went on to add:

And the second reason that I’m worried about this is that science is more than a body of knowledge. It’s a way of thinking. A way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then we’re up for grabs for the next charlatan political or religious who comes ambling along.

This brings to my mind one of favourite Carl Sagan quotes:

The Open Culture article concludes:

“Nearly 30 years later, we have reached this point. Under the second Trump administration, DOGE has rushed to dismantle the scientific infrastructure of the US government, haphazardly cutting the National Science Foundation, the National Institutes of Health, and NASA. Next, they’re going after leading research universities, intentionally weakening the research engine that has fueled the growth of American corporations—and the overall American economy—since World War II. And they’re replacing scientific leaders with charlatans like RFK Jr. who dabble in the very pseudoscience that Sagan warned us about. Needless to say, our competitors aren’t making the same mistakes. Few serious governments are stupid enough to cut off their nose to spite their face.”

Carl Sagan was not just a brilliant scientist and a thoroughly decent human being, he was a prophet!

First and foremost, for me, he was a brilliant, inspirational communicator of difficult concepts. I first encountered him in my first year at University, when the BBC screened his exquisite series “Cosmos: A Personal Voyage (with Carl Sagan)” (13 episodes, 1980/81).

Thankfully, the whole series is still available to us all. https://archive.org/details/CosmosAPersonalVoyage/1980+Cosmos+(A+Personal+Voyage)+-+Ep+01+The+Shores+of+the+Cosmic+Ocean.mp4

If you are not inclined to watch it all, at least watch the first 10 minutes or so. I wager many of you will be drawn in by his voice and words and end up watching more. But whatever; you will get the feel for what drew me in.

At the very least, spare three and a half minutes to watch this video that presents the essence of my worldview so beautifully.

I find it even more powerful when I read it slowly to myself:

From this distant vantage point [that of ‘an alien scientist newly arrived at the

outskirts of our solar system’ where Voyager 1 took the photograph], the Earth

might not seem of any particular interest.

But for us, it’s different. Look again at that dot. That’s here. That’s home. That’s

us. On it everyone you love, everyone you know, everyone you ever heard of, every

human being who ever was, lived out their lives. The aggregate of our joy and

suffering, thousands of confident religions, ideologies, and economic doctrines,

every hunter and forager, every hero and coward, every creator and destroyer of

civilization, every king and peasant, every young couple in love, every mother and

father, hopeful child, inventor and explorer, every teacher of morals, every

corrupt politician, every ‘superstar,’ every ‘supreme leader,’ every saint and

sinner in the history of our species lived there — on a mote of dust suspended in a

sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of

blood spilled by all those generals and emperors so that, in glory and triumph,

they could become the momentary masters of a fraction of a dot. Think of the

endless cruelties visited by the inhabitants of one corner of this pixel on the

scarcely distinguishable inhabitants of some other corner, how frequent their

misunderstandings, how eager they are to kill one another, how fervent their

hatreds.

Our posturings, our imagined self-importance, the delusion that we have some

privileged position in the Universe, are challenged by this point of pale light. Our

planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in

all this vastness, there is no hint that help will come from elsewhere to save us

from ourselves.

The Earth is the only world known so far to harbour life. There is nowhere else, at

least in the near future, to which our species could migrate. Visit, yes. Settle, not

yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience.

There is perhaps no better demonstration of the folly of human conceits than this

distant image of our tiny world. To me, it underscores our responsibility to deal

more kindly with one another, and to preserve and cherish the pale blue dot, the

only home we’ve ever known.

If he were still around today, he would be appalled, but sadly not shocked. As I am. As many of you, no doubt, are too. The question is, what are we going to do about it? The very least that we can all do is take on board the last sentence of ‘The Pale Blue Dot’:

To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.

Amen.