Friday, April 19, 2024

The Psychology of Conspiracy Theories

Presented by Zelda Gilbert, Retired professor of psychology

May 4, 2024, 1:30pm

Central Library
Barbara M. Donnellan Auditorium
1015 North Quincy Street
Arlington, VA [map] [directions]
(Virginia Square-GMU Metro station)
FREE admission – Everyone welcome, members and non-members

 Also a YouTube Live Event with Q and A 

NCASVideo YouTube Channel:  (corrected URL)

Dr. Gilbert will discuss how the tools of modern psychology can be used to explore the prevalence, motivations, and content of historical and contemporary conspiracy theories. This will include conspiracy theories concerning such things as Lincoln’s assassination, chemtrails, the destruction of the battleship Maine, election fraud, and space lasers from orbit. Concepts such as existential, epistemic and socio-psychological motivations will be defined and applied to various theories, providing the audience with the tools to do their own analyses. Finally, audience members will be invited to create and evaluate their own conspiracy theories.

Zelda Gilbert is a retired professor of psychology with over 40 years experience in higher education. She currently lectures on  political psychology, conspiracy theories, and other topics, mostly for the continuing education Silver Frogs program at Texas Christian University in Fort Worth. She completed a doctorate in counseling psychology at the University of Kentucky and studied political psychology at UCLA. 

Tuesday, April 02, 2024

Cancer Risk Assessment, Its Wretched History and Its Impact on Public Health

Presented by 

Edward J. Calabrese, Professor of Toxicology at the University of Massachusetts, 

School of Public Health and Health Sciences, Amherst.

April 13, 2024, 1:30-3:00pm

On YouTube, (

The historical foundations of cancer risk assessment were based on fundamental scientific errors that were never corrected, all within the framework of an extraordinary appeal to the authority of the radiation genetics community, led by Hermann J Muller. Even though these individuals were greatly talented and accomplished, they were driven by ideological and self-serving professional biases that would lead to both falsification of the research record and suppression of key scientific findings, all in an effort to establish the linear no-threshold (LNT) model for hereditary and cancer risk assessment, replacing the threshold dose response model. This troubling history has now been revealed in a long series of peer reviewed publications by the author and summarized in a 22-episode documentary by the Health Physics Society* ( This troubling history remained hidden from the regulatory agencies around the globe since their inception. These groups simply and uncritically accepted a flawed and corrupt history, assuming that it was accurate and reliable. Yet, this path of historical ignorance led the US EPA, and other national regulatory agencies, to accept a dishonest foundation upon which to base and frame cancer risk assessment, terribly failing in their public service mission. This untenable situation has placed a continuing stranglehold on the actions of all regulatory agencies worldwide, improperly guiding its philosophies, policies and practices down to the present time.

(*Note that the views expressed in these videos do not necessarily represent official positions of the Health Physics Society.)

Edward J. Calabrese is a Professor of Toxicology at the University of Massachusetts, School of Public Health and Health Sciences, Amherst. Dr. Calabrese has researched extensively in the area of host factors affecting susceptibility to pollutants, and is the author of over 1,000 papers in scholarly journals, as well as more than 10 books. Dr. Calabrese was awarded the 2009 Marie Curie Prize from the World Council of Nuclear Workers for his body of work on hormesis. He was the recipient of the International CCN Society's Springer award for 2010. He was awarded an Honorary Doctor of Science Degree from McMaster University in 2013. In 2014 he was awarded the Petr Beckmann Award from Doctors for Disaster Preparedness. Dr. Calabrese was awarded the G. William Morgan Lectureship Award and the Robert S. Landauer, Sr., Lectureship Award in 2022 from the Health Physics Society.

Shadow of a Doubt - March 2024


  • Lecture March 9 - Brian Dunning  presents  a discussion of "The UFO Movie They Don't Want You to SEE"
  • Eldrich investigations and a discount for NCAS
  • April NCAS Lecture - Edward Calabrese will discuss "linear no-threshold" (LNT) model, an ionizing radiation dose-response model used in radiation protection.  How accurate is the model for estimating cancer risk at low doses?  Saturday, April 13 at 1:30 PM ET, live on the NCASVideo YouTube channel.
  • March PhACT lecture - "Explorations into the Age of Fishes and the Origin of Limbed Vertebrates"
  • March Bay Area Skeptics - Paul A. Offit, MD, Director of the Vaccine Education Center at the Children's Hospital of Philadelphia as well as the Maurice R. Hilleman Professor of Vaccinology and a Professor of Pediatrics at the Perelman School of Medicine at the University of Pennsylvania, will present "COVID Myths: And the Hits Just Keep on Comin'."
  • Videos from CSICON 2023
  • "Spring Forward" - NCAS discussion of daylight savings time controversy
  • NCAS membership
  • Shadow Light
  • Time to Renew
See the complete March 2024 Shadow

Shadow of a Doubt - March 2024


March 2024

NCAS Public Lecture Series

A Discussion of "The UFO Movie THEY Don't Want You to See"

 YouTube Live Event with Q and A 

Brian Dunning
Executive Producer / Writer / Presenter, The UFO Movie THEY Don't Want You to See

Saturday, March 9, 1:30pm US/Eastern (UTC-05:00)
NCASVideo YouTube Channel:

This month, NCAS presents a different kind of event. We invite you to watch The UFO Movie THEY Don't Want You to See BEFORE March 9, 2024 (see below for how to watch). Then join us on Saturday, March 9 at 1:30 PM ET for an online Q & A with Executive Producer / Writer / Presenter Brian Dunning.

From the film's website:

"In an age when misinformation, alternative facts, and conspiracy theories have become mainstream, UFOs have risen to become one of the most-talked about pop culture phenomena. With all of this noise, how can we expect anyone to know how much of this is true? What is in our skies? What do we know, and how do we know it? And most importantly: Are we being visited?

Science does have most of these answers, and we're working on answering the rest of them. Featuring experts in cosmology, physics, and image analysis, The UFO Movie THEY Don't Want You to See will lay out for you exactly what we know and how we know it."

Science writer Brian Dunning is a documentary filmmaker and the host of Skeptoid, the award-winning weekly science podcast. Since 2006, Skeptoid has been revealing the true science behind popular misinformation and urban legends. Dunning's recent movies include the educational film Principles of Curiosity (2017) and the feature documentary Science Friction (2022) revealing the deceptive editing that sometimes happens to science experts on mainstream television programs. He is a member of the National Association of Science Writers.

Full information about this documentary, including streaming services that carry it, can be found at

To watch the film for free (with ads), use this link:

How to Watch and Participate in this Online Discussion Event:

1) Use a supported browser...
2) Use the link
3) The live stream begins shortly before 1:30pm US/Eastern (UTC-05:00) on Saturday, March 9, 2024.
4) To post questions, you must be signed in to a Google account.
5) Post your questions in the chat window to the right of the video player when the live stream is active.
6) Click into where it says "Say something..." and begin typing (up to 200 characters). Then click the send icon .

Along with your question, please post what city or town you're in.

How to Watch and Participate in an Online Viewing Event:

Of course, you can watch the movie on your own.  Or, if you prefer a shared experience, there will be an online viewing event on Wednesday, March 6 at 7:30 PM ET.

1) Check your email inbox (the same one that's receiving this Shadow of a Doubt) at 6:45 PM ET on Wednesday, March 6.
2) Click on the "Watch2Gether" link in the email.  Your browser will display our "room" to watch the movie on YouTube together.
3) Start typing in the chat window at the right of the screen.  The documentary will start at 7:30 PM sharp, but anyone who wants to hang out there before showtime is welcome.  At 7 PM, the main feature will be preceded by a short "documentary" (one of the 1970s fake documentaries that we can laugh at).
4) Webcams and microphones won't be active, just the chat window.  Get ready to type!

Eldritch Investigations and a Discount for NCAS
"Cults and cryptids collide when a curious Washingtonian investigates local unexplained phenomena.  Explore the lure of the unknown and its entanglement with DC history in this multi-chapter adventure across the city."

At the start of the pandemic, the local Rorschach Theatre company created a unique theatrical experience that extended over the course of 9-10 months. It was originally a way for the show to go on when the pandemic shut down stage performances, but it has been so successful that they've continued into their 4th year with an all-new story in December 2023.

Rorschach often incorporates elements of fantasy, horror, and/or supernatural. This coming season the Eldritch Investigations project involves themes particularly close to NCAS. The company has extended a 20% discount to NCAS members.

Subscribers receive a monthly box or envelope with maps, directions to locales around DC, and other artifacts such as postcards, telegrams, and various trinkets that help unfold a story over the course of 9-10 months. You investigate these locations at your own pace, on your own time. They also provide online videos for those who can't visit in person.

The adventure has already begun, so new subscribers will receive all previous chapters in the first shipment.

For the discount, use code NCAS when subscribing here:

Sounds a bit like an expanded version of our NCAS Skeptours!

April NCAS Event
Edward Calabrese, Professor of Environmental Health Sciences at the University of Massachusetts Amherst School of Public Health and Health Science, will discuss the "linear no-threshold" (LNT) model, an ionizing radiation dose-response model used in radiation protection.  How accurate is the model for estimating cancer risk at low doses?  Saturday, April 13 at 1:30 PM ET, live on the NCASVideo YouTube channel.

Ahead of his presentation, Professor Calabrese recommends watching videos describing the historical foundations of cancer risk assessment, hosted on the Health Physics Society YouTube page:

Note: the 22 episodes total several hours, but can be expedited by adjusting the playback speed to 1.25x, 1.5x, 1.75x, or 2x.

March PhACT Lecture
Our skeptical neighbors to the north, the Philadelphia Association for Critical Thinking (PhACT), will host their next online event on Saturday, March 16 at 2 PM ET.  Paleontologist Ted Daeschler, PhD will present "Explorations into the Age of Fishes and the Origin of Limbed Vertebrates," describing three decades of paleontological exploration and research on Late Devonian (385-365 million years ago) fossils from Pennsylvania, the high Canadian Arctic and Antarctica.  Event details at

March Bay Area Skeptics Lecture
The [San Francisco] Bay Area Skeptics will host their next online event on Thursday, March 14 at 9 PM ET.  Paul A. Offit, MD, Director of the Vaccine Education Center at the Children's Hospital of Philadelphia as well as the Maurice R. Hilleman Professor of Vaccinology and a Professor of Pediatrics at the Perelman School of Medicine at the University of Pennsylvania, will present "COVID Myths: And the Hits Just Keep on Comin'."  The continued onslaught of myths and misinformation surrounding COVID and COVID vaccines has been unrelenting and contributes to the low uptake of this vaccine. Dr. Offit will try to debunk some of these myths and put them in context.  This will be livestreamed on YouTube:

Lessons Learned from the COVID-19 Pandemic Response
Dr. Offit recently discussed his new book Tell Me When It's Over (National Geographic, 2024) with Michael Shermer.  In his book, Dr. Offit presents a "lessons learned" perspective on the response to the COVID-19 pandemic, based on his experience as a member of the FDA Vaccine Advisory Committee and a former member of the Advisory Committee for Immunization Practices to the CDC.  His discussion with Dr. Shermer is available at

Later, Dr. Offit also responded to the following two questions/comments from NCAS President Scott Snell:

So much of the mask debate was the claim that one cannot adequately protect oneself by wearing a mask; others must also wear masks to protect oneself.

Was that true after N95 masks became generally available to the public?  I assume there was excellent data about COVID history of health care workers (presumably using the best masks and trained to use them properly).  The workers had to take care of very sick/contagious unmasked patients indoors for long periods of time.  How sick did the workers get?

If (as I assume) they did not often get sick, did that suggest that all of us "civilians" could essentially imitate the success of health care workers?  Moreover, this could've been an excellent "panpartisan" meme.  Nurses and many other health care workers were seen (and still are) as heroes.  "Let's imitate the health care heroes, wear your mask to protect yourself!  Here's how to wear your mask correctly [etc]."  This would, I think, largely avoid the "you've got to wear a mask to protect me" meme that caused so much (unnecessary?) controversy.  What are your thoughts about this?

In conversation (paraphrased and printed here with his permission), Dr. Offit responded that this might've been a worthwhile approach to depolarizing the masking issue.  Unfortunately the N95 masks (generally upper 90s percent effective at blocking virus-laden droplets), KN95 (lower 90s percent effective), and surgical masks (80s percent effective) were not available to the public in the early months of the pandemic.  But once these better masks were available, anyone with proper training could adequately protect themselves without insisting that others wear masks too.

Regarding achieving COVID herd immunity via vaccination, what was the percentage required?  If it was, say, 80%, was one societal possibility to offer a "lottery" for anyone who didn't want the vaccine?  That way, perhaps many if not all objectors could be exempted from vaccination, if they won the lottery.  (The number of lottery victors could be as many as 20% of the community in my example.)

Dr. Offit's response, described in more detail in his book, is that the vaccination mandates caused a backlash that probably reduced COVID vaccination rates and now have spilled over to a push back against all vaccine mandates, including school vaccine mandates.  Rather than using mandates (or the suggested exemption lottery), educating the public is the best way to maximize vaccination rates.

Videos from CSICon 2023
Center for Inquiry has recently posted the Richard Dawkins lecture, "Science, the Poetry of Reality, Jewel in Humanity’s Crown" on its YouTube site:

Writing in the November 2023 Shadow of a Doubt, NCAS Board Member Curtis Haymore called it "really wonderful, deeply thoughtful, filled with his well-crafted language."

Also recently added was a conversation between Dawkins and Bill Nye, who received the 2023 Richard Dawkins Award for proclaiming "the values of secularism and rationalism, upholding scientific truth wherever it may lead."

"Spring Forward"
On Sunday, March 10, most of the United States and Canada will make the customary change from Standard Time to Daylight Saving Time.  Three weeks later, most of Europe will follow suit.

Back and forth we go.  Are you tired (literally tired) of switching your clocks one hour back every Fall and one hour forward every Spring? Why do we go to all the trouble?  Do we have any good alternatives?  What's been tried before, or tried elsewhere?  See "The Times They Are(n't) a-Changin'" on the NCASVideo YouTube site:

NCAS Membership
At its September 20, 2023 meeting, the NCAS Board of Directors approved a change in membership classifications, effective October 1.  Formerly in two classifications, Single and Double, membership now comprises one or two individuals at the same home address.  In addition to simplifying transactions for the NCAS treasurer, this represents a per-person reduction in membership costs.  The former Single membership cost now covers up to two people.  Consider adding a 2nd person in your household to your NCAS membership at no extra cost!  Both will be able to vote separately in the annual NCAS board of directors election.  Send an email to to add a 2nd person to your membership.  We hope to add members, and of course a student or other young person is always welcome for the future of skepticism.  Also see

Shadow Light
Some members and contacts of NCAS receive a postal notification of this and every new monthly Shadow of a Doubt.  The Shadow Light postcard announces the monthly lecture and highlights of the electronic Shadow of a Doubt, which is available online at  NCAS thereby reduces Shadow production and postage costs.  To further reduce costs, members and contacts can opt out of postal notification altogether, while continuing to receive Shadow of a Doubt via e-mail.  To opt out, send us an e-mail at

Time to Renew?
Be sure to check your renewal date above your postal address on the Shadow Light postcard. Send any queries to  Use the online membership form to renew.