Why I strongly disagree with the interdimensional hypothesis of the UFO phenomenon

by Spartacus01

According to Jacques Vallée and the late John Keel, UFOs aren’t spacecraft from other planets, but manifestations of entities from other dimensions or realities that coexist with our own. These entities, they argue, have interacted with human beings throughout history. Rather than showing their true form, assuming such a thing even exists, they supposedly adjust their appearance and behavior to match the cultural beliefs and expectations of each period. In other words, they appear in ways that reflect what people expect to see, based on the dominant worldview of the time.

For example, in ancient times and the Middle Ages, when society was deeply influenced by religion and mythology, people were inclined to interpret strange encounters as experiences involving angels, demons, spirits, or fairies, so the entities presented themselves in those forms because that was what people could understand. In the modern era, shaped by science fiction and technological progress, the same entities supposedly appear as extraterrestrial beings piloting advanced craft. From this perspective, the phenomenon is real but not extraterrestrial. Instead, it’s a timeless, shape-shifting presence that influences human perception according to the beliefs and expectations of each historical period.

Many people find this hypothesis intriguing, and I get why it appeals to those who like symbolic or mythological explanations. However, I don’t share that view. I believe the theory collapses under close examination for several important reasons, and I want to explain why.

The fundamental difference between ancient folklore and modern UFO sightings is the presence of evidence. Old stories about angels, spirits, demons, and fairies are simply that: stories. There’s no concrete or verifiable evidence that any of those encounters actually occurred, let alone that the described entities were real. In contrast, modern UFO cases provide physical and measurable data. We have radar-visual cases where unidentified objects were both tracked on radar and seen by witnesses. We have ground traces left at alleged landing sites, such as scorched soil, flattened vegetation, and sometimes chemical or molecular alterations of the environment. We also have pilot reports, military documentation, cases of electromagnetic interference, and sightings confirmed by multiple independent witnesses. So it makes no sense to lump modern, well-documented cases together with ancient myths and legends that have no supporting evidence.

Furthermore, just because ancient people described unusual objects moving in the sky doesn’t mean they were seeing the same things we call UFOs today. In ancient and medieval times, people had little to no understanding of celestial phenomena such as meteorites, bolides, shooting stars, sundogs, ball lightning, and so on. So it was natural that whenever they saw something unusual in the sky, they interpreted it as something mystical or divine, often describing it in vivid, highly imaginative ways that didn’t necessarily reflect what they actually saw. Moreover, many stories about sky gods, fiery chariots, winged creatures, or flying wooden ships can simply be traced back to humanity’s fascination with flight. From the moment people first observed birds and insects soaring through the air, they dreamed of doing the same. Humans have always been interested in flight, so it’s natural that ancient civilizations developed myths that revolved around that concept. These tales shouldn’t be read as real encounters with non-human entities, but as expressions of human imagination. Interpreting them as literal accounts of real experiences ignores decades of anthropological research and completely overlooks the cultural context in which they were created. Not every pre-1947 account that mentions something flying should be assumed to describe something real.

Therefore, I believe there’s no valid reason to assume that ancient folkloric accounts and modern UFO reports originate from the same source. Arguing that a few superficial similarities between old legends and modern UFO encounters prove a common origin isn’t logic supported by evidence; it’s simply an unfounded leap of imagination.

Finally, a major problem with the interdimensional hypothesis is the way Vallée and Keel approached the evidence. Rather than critically evaluating individual reports, they treated virtually all sightings, landing cases, and creature encounters as equally important without carefully filtering them. For example, Vallée’s Passport to Magonia relied heavily on cases taken from old newspaper clippings, many of which lacked proper verification or came from sources known for hoaxes and exaggerations. They argued that the totality of all reports needed to be explained by a single theory, which led them to create a model so broad and all-encompassing that it ultimately explains everything and therefore explains nothing. Instead of acknowledging that some apparently solid reports might actually be the result of misperceptions or outright fabrications, they tried to account for the diversity and inconsistency of the reports by assuming that the interdimensional intelligence behind the phenomenon can alter human perception so that any contradiction can be easily explained away.

Is there a UFO report where one witness describes a disc-shaped object while another describes a triangular one? They’re not lying; it’s the intelligence behind the phenomenon that decided to appear one way to one witness and a completely different way to the other. Does radar pick up a solid object moving at high speed while pilots report seeing a small, slow-moving light? That’s not a mistake or equipment error; it’s the intelligence presenting itself differently to the radar operators and the pilots. In this way, every contradiction, every mismatch between witnesses, instruments, and physical traces becomes part of the plan, which makes it impossible to disprove the hypothesis. This is the exact opposite of the scientific method, because genuine scientific hypothesis must be open to being proven wrong, and that’s something that simply can’t be done in this case.

Overall, the hypothesis doesn’t hold up when you look at the full picture. It treats myths and folklore as if they were evidence, ignores the possibility of misperceptions, errors, or outright hoaxes, and explains contradictions through the actions of an all-powerful, shape-shifting intelligence. It makes the phenomenon impossible to study in any meaningful way, which is exactly the opposite of what a scientific hypothesis should do. By contrast, the extraterrestrial hypothesis offers a more solid framework, because it focuses on tangible evidence, measurable phenomena, and testable claims. It makes it possible to evaluate, confirm, or refute reports rather than relying on an unfalsifiable assumption to explain every inconsistency.