Uploaded July 2016 | Updated September 2026, 1 hour ago
Presented by Thomas Holtz as part of the Skeptical Thinking Track at Balticon 50 on May 30, 2016.
Did Atlantis really exist? What about Lemuria? Could the Earth be hollow—or even concave? In this eye-opening talk, Dr. Thomas R. Holtz Jr. dives deep into the surprising history of paranormal ideas within the Earth sciences, from ancient myths to pseudoscientific claims and speculative fiction. If you're curious about how science confronts fantastical claims with evidence, this is a must-watch.
From lost continents and drowned civilizations to bizarre hollow Earth theories and plankton-based origin myths, Dr. Holtz explores a wide range of fringe beliefs that touch on geology, paleontology, and planetary science. Using a mix of historical research, scientific context, and skeptical inquiry, he guides viewers through the fascinating intersection of pseudoscience, science fiction, and legitimate geoscience.
Dr. Holtz begins by examining the enduring myth of Atlantis, tracing its origin not to archaeological finds but to the writings of Plato, who used it as a political allegory. Although widely misunderstood as a “myth,” Atlantis first appeared in Plato’s dialogues—the Critias and the Timaeus—as an imaginative exercise in alternative history. The talk delves into how later thinkers like Ignatius Donnelly, a 19th-century U.S. Congressman, reinterpreted Atlantis as a lost high civilization and ancestral homeland to cultures around the world. Donnelly’s pseudoscientific claims sparked modern occult movements and influenced science fiction authors such as Jules Verne, J.R.R. Tolkien, and Edgar Cayce.
The presentation then moves to Lemuria, a “lost continent” invented by 19th-century scientists to explain the biogeographical distribution of lemurs. Though once a plausible geological hypothesis, Lemuria was soon debunked with the advent of plate tectonics. However, it gained a second life in theosophy and New Age spiritualism, thanks to figures like Madame Blavatsky, who envisioned Lemuria as the homeland of a pre-human “root race.” Lemuria continues to appear in pop culture, including Marvel Comics and esoteric belief systems.
Doggerland, Beringia, Sunda, and Zealandia—real examples of submerged landmasses from the last Ice Age—are presented in contrast to these myths. These scientifically supported cases of sea-level rise and land bridge formation during glacial periods show how careful geologic research helps distinguish reality from romanticized pseudoscience.
The video also covers the Hollow Earth hypothesis, beginning with early models like Athanasius Kircher’s subterranean chambers and Edmund Halley’s nested spheres. These ideas, meant to explain magnetic anomalies and geothermal activity, were later expanded by American eccentric John Cleves Symmes Jr., who proposed “Symmes holes” at the poles and an inhabitable inner world lit by a central sun—precursors to countless science fiction tales like Edgar Rice Burroughs' Pellucidar.
Even more extreme theories are explored, such as Cyrus Teed’s concave Earth belief, which held that humanity lives on the inside surface of a hollow sphere. His followers constructed elaborate measuring devices like the “Rectilineator” to prove their theory—a failed but intriguing example of pseudoscientific experimentation.
Finally, the presentation ends with the truly peculiar case of Randolph Kirkpatrick, a scientist who became convinced that all rocks—volcanic, sedimentary, even meteorites—were composed of giant single-celled plankton called Nummulites. His personal theory turned Earth science on its head, replacing the rock cycle with a biosphere built from ancient foraminifera.
About the Speaker:
Dr. Thomas R. Holtz Jr. is a vertebrate paleontologist and Principal Lecturer in the Department of Geology at the University of Maryland, College Park. He specializes in theropod dinosaurs and the history of paleontological science. Dr. Holtz is the author of Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages and a recognized authority on evolution, science communication, and scientific skepticism.
The views expressed in this presentation are those of the speaker and do not necessarily reflect the views of the National Capital Area Skeptics (NCAS).
#Atlantis #Lemuria #HollowEarth #Pseudoscience #Skepticism #ScienceEducation #Geology #Paleontology #MadameBlavatsky #IgnatiusDonnelly #Doggerland #SymmesHole #ConcaveEarth #Foraminifera #ParanormalClaims #CriticalThinking #ScientificSkepticism #ScienceVsPseudoscience #ScienceLiteracy #AlternativeHistory #AncientAliensDebunked #PlatoAtlantis #EdgarCayce #FlatEarth #Pellucidar #EarthScienceMyths #MythologyVsScience #NewAgeBeliefs #ScienceAndSpeculation #Balticon2025 #NCAS #DrThomasHoltz #GeologicalSkepticism #ScienceFictionAndFact #LostCivilizations #SeaLevelRise #Zealandia #Beringia #SundaLand #SunkenContinents #FantasyVsReality #TolkienAtlantis #HistoryOfScience
Presented by Thomas Holtz as part of the Skeptical Thinking Track at Balticon 50 on May 30, 2016.
Did Atlantis really exist? What about Lemuria? Could the Earth be hollow—or even concave? In this eye-opening talk, Dr. Thomas R. Holtz Jr. dives deep into the surprising history of paranormal ideas within the Earth sciences, from ancient myths to pseudoscientific claims and speculative fiction. If you're curious about how science confronts fantastical claims with evidence, this is a must-watch.
From lost continents and drowned civilizations to bizarre hollow Earth theories and plankton-based origin myths, Dr. Holtz explores a wide range of fringe beliefs that touch on geology, paleontology, and planetary science. Using a mix of historical research, scientific context, and skeptical inquiry, he guides viewers through the fascinating intersection of pseudoscience, science fiction, and legitimate geoscience.
Dr. Holtz begins by examining the enduring myth of Atlantis, tracing its origin not to archaeological finds but to the writings of Plato, who used it as a political allegory. Although widely misunderstood as a “myth,” Atlantis first appeared in Plato’s dialogues—the Critias and the Timaeus—as an imaginative exercise in alternative history. The talk delves into how later thinkers like Ignatius Donnelly, a 19th-century U.S. Congressman, reinterpreted Atlantis as a lost high civilization and ancestral homeland to cultures around the world. Donnelly’s pseudoscientific claims sparked modern occult movements and influenced science fiction authors such as Jules Verne, J.R.R. Tolkien, and Edgar Cayce.
The presentation then moves to Lemuria, a “lost continent” invented by 19th-century scientists to explain the biogeographical distribution of lemurs. Though once a plausible geological hypothesis, Lemuria was soon debunked with the advent of plate tectonics. However, it gained a second life in theosophy and New Age spiritualism, thanks to figures like Madame Blavatsky, who envisioned Lemuria as the homeland of a pre-human “root race.” Lemuria continues to appear in pop culture, including Marvel Comics and esoteric belief systems.
Doggerland, Beringia, Sunda, and Zealandia—real examples of submerged landmasses from the last Ice Age—are presented in contrast to these myths. These scientifically supported cases of sea-level rise and land bridge formation during glacial periods show how careful geologic research helps distinguish reality from romanticized pseudoscience.
The video also covers the Hollow Earth hypothesis, beginning with early models like Athanasius Kircher’s subterranean chambers and Edmund Halley’s nested spheres. These ideas, meant to explain magnetic anomalies and geothermal activity, were later expanded by American eccentric John Cleves Symmes Jr., who proposed “Symmes holes” at the poles and an inhabitable inner world lit by a central sun—precursors to countless science fiction tales like Edgar Rice Burroughs' Pellucidar.
Even more extreme theories are explored, such as Cyrus Teed’s concave Earth belief, which held that humanity lives on the inside surface of a hollow sphere. His followers constructed elaborate measuring devices like the “Rectilineator” to prove their theory—a failed but intriguing example of pseudoscientific experimentation.
Finally, the presentation ends with the truly peculiar case of Randolph Kirkpatrick, a scientist who became convinced that all rocks—volcanic, sedimentary, even meteorites—were composed of giant single-celled plankton called Nummulites. His personal theory turned Earth science on its head, replacing the rock cycle with a biosphere built from ancient foraminifera.
About the Speaker:
Dr. Thomas R. Holtz Jr. is a vertebrate paleontologist and Principal Lecturer in the Department of Geology at the University of Maryland, College Park. He specializes in theropod dinosaurs and the history of paleontological science. Dr. Holtz is the author of Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages and a recognized authority on evolution, science communication, and scientific skepticism.
The views expressed in this presentation are those of the speaker and do not necessarily reflect the views of the National Capital Area Skeptics (NCAS).
#Atlantis #Lemuria #HollowEarth #Pseudoscience #Skepticism #ScienceEducation #Geology #Paleontology #MadameBlavatsky #IgnatiusDonnelly #Doggerland #SymmesHole #ConcaveEarth #Foraminifera #ParanormalClaims #CriticalThinking #ScientificSkepticism #ScienceVsPseudoscience #ScienceLiteracy #AlternativeHistory #AncientAliensDebunked #PlatoAtlantis #EdgarCayce #FlatEarth #Pellucidar #EarthScienceMyths #MythologyVsScience #NewAgeBeliefs #ScienceAndSpeculation #Balticon2025 #NCAS #DrThomasHoltz #GeologicalSkepticism #ScienceFictionAndFact #LostCivilizations #SeaLevelRise #Zealandia #Beringia #SundaLand #SunkenContinents #FantasyVsReality #TolkienAtlantis #HistoryOfScience
