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Dimensions: A Casebook of Alien Contact

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EXPLORING OTHER DIMENSIONS


In DIMENSIONS, Dr. Jacques Vallee reexamines the historical record that led to the modern UFO phenomenon and to the belief in alien contact. He tackles the enigma of abduction reports, which come from various times and various countries, as well as the psychic and spiritual components of the contact experience. He notes the factors that inhibit research into the phenomenon and concludes that the extraterrestrial theory is simply not strange enough to explain the facts. A serious scientist who has studied the phenomenon of alien contact stories examines past and present claims and offers the startling hypothesis that they are true, but that the reported "beings" are not from other planets or galaxies, that they may inhabit another dimension, a dimension so startlingly different from our own that our consciousness lurches to experience it.

311 pages, Mass Market Paperback

First published January 1, 1988

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About the author

Jacques F. Vallée

66 books388 followers
Excerpted from wikipedia: Jacques Fabrice Vallée (born September 24, 1939 in Pontoise, Val-d'Oise, France) is a venture capitalist, computer scientist, author, ufologist and former astronomer currently residing in San Francisco, California.
In mainstream science, Vallée is notable for co-developing the first computerized mapping of Mars for NASA and for his work at SRI International in creating ARPANET, a precursor to the modern Internet. Vallée is also an important figure in the study of unidentified flying objects (UFOs), first noted for a defense of the scientific legitimacy of the extraterrestrial hypothesis and later for promoting the interdimensional hypothesis.

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124 (14%)
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Displaying 1 - 30 of 66 reviews
Profile Image for MacWithBooksonMountains Marcus.
355 reviews16 followers
March 1, 2024
Amazing. Vallee is a professional through and through. He reminds me on Joseph Campell and his grand mono myth theory. Vallee also tries to find common denominators in the making of myth from miracles. He is looking very closely at such phenomena as they occurred at Lourdes and Fatima where he finds similarities to more modern UFO sightings. All in all, an entirely new take on and attempt to make sense of the whole UFO shebang including sightings and abductions. All beautifully written and quite believable.
Profile Image for Mark Tallen.
267 reviews15 followers
January 30, 2018
Highly recommended for anyone interested in Ufology. This book explores the possibility that UFOS whilst a reality, are not extraterrestrial in nature but are related to another dimension. A dimension that has had impact on and influenced the human consciousness for thousands of years through its pyshical and psychological nature. Vallee followed this book with Confrontations and then Revelations.
Profile Image for Brent.
91 reviews1 follower
April 1, 2013
I was reading Lights in the Sky & Little Green Men and this book was referenced several times so I decided to take a look at it. Part of my curiosity was that Hugh Ross was writing from a Christian perspective and I was sure that Jacques Vallee would not be approaching the subject from that angle.

It is interesting to not the they come to similar conclusions. Of interest:

1. Vallee argues that we cannot view the UFO phenomena as an isolated modern event. He links UFO accounts with folklore, mythology, religion. I think he does a good job showing that there are many similarities between UFO abductions and fariey abductions, etc.

The only spot that seemed weak in this section was his handling of archaeology.

2. On his own he comes to some sort of 'gods of the nations' theory.

3. The information given by the creatures people see is often deceptive or full of half truths.

4. Much of it appears to be a system of control, designed to isolate people, make people look absurd/foolish, change their worldview.

I don't think he ever used the term 'politics' but it would be fitting.

6. If you have read any scholary books about the fairyfaith you will know the key to seeing the fairy is that it is a 'meeting,' even if it looks like you took them by suprise you only saw them because it was their purpose.

Vallee thinks that a lot of UFO sightings are staged in the same way.

7. He rejects the extraterrestrial theory and has several good points. Of interest is that most 'aliens' seen have more to do with the Earth's biosphere than one would expect of a truely alien lifeform.

And so on.
Profile Image for Aja Miller-arrow.
18 reviews3 followers
June 30, 2015
Jacques F Vallee was at the frontier of ufology from its inception in the 1950's and is one of the most credible and well-respected researchers in the field. Passport to Magonia and this book, Dimensions: A Casebook of Alien Contact, share his changed opinion that the UFO phenomena is not caused by extraterrestrials. Vallee urges scientists to seriously study the phenomena without jumping too quickly to the wrong hypothesis that aliens are behind it. Vallee distances himself from the Chariots of Fire, Ancient Aliens sect of believers and cautions against the Harmonic Convergence that has resulted from New Age thought. I would highly recommend anyone interested in UFOs to read Dimensions and the two books that follow it.
5 reviews
December 24, 2020
The books is highly informative and it will really change how you see UFO news. We are still jumping to the same old conclusions we did 50 years ago. I would have loved more information about the particular cases, but then it would have been a really long book.
Profile Image for Stephanie Sanders-Jacob.
Author 6 books57 followers
June 7, 2022
I can’t believe I’m giving Jacques Vallée three stars but here we are. Maybe if I hadn’t read Passport to Magonia I would have enjoyed this more. I felt like there was a lot of recycled content.

The supposed main claim of this book is that UFOs are not extraterrestrial, but are instead extradimensional. It’s a cool theory and deserves just as much consideration as the outer space idea, but the topic is mostly relegated to the last third of the book, with the first two sections trying to convince the reader that UFOs are real and have been seen across the centuries. In my mind, if someone is reading this book, they’ve already come to that conclusion. I guess I just wanted to see more of the theories behind alternate dimensions than rudimentary proof of UFOs. Especially when a lot of that is already covered in his earlier books.
Profile Image for no.stache.nietzsche.
124 reviews32 followers
October 2, 2023
First in a series and second of Vallee's audiobooks that we've read. He has a very interesting take on the UFO phenomenon, essentially that they are neither a hoax nor extraterrestrial, but terrestrial entities, very much physical (not physic projections, as Jung hypothesized), and in the same lineage as "the fae", fairy folk, religious encounters with angels and demons, etc. At least in some regard, this seems highly plausible, given the continuity of evidence that Vallee lays out. JR Jorjani's thesis in Closer Encounters essentially builds off Vallee's work, and this empirical foundation is definitely worth taking a look at.
Profile Image for Darren.
24 reviews2 followers
December 25, 2019
In my opinion, of all the books that have been written addressing UFOs and the Phenomenon in general, it is Vallee's outside-the-box thinking that hits closest to the mark. And of Vallee's many excellent contributions, this one is one of my favorites.
Profile Image for Barb.
939 reviews55 followers
May 16, 2023
This was a crazy book that ended up making a lot of sense.
Profile Image for Mike.
1,429 reviews55 followers
October 18, 2023
I read this book with an open mind and high expectations, as Vallée is considered one of the biggest authorities on UFO lore. I certainly don’t think humans are the lone intelligence in the cosmos, and I think it’s quite possible that Earth has been visited, at the very least, by advanced intelligence. So count me among the “I WANT TO BELIEVE” crowd – a skeptic who is becoming more open to other possibilities.

That being said, two-thirds of this book was a disappointing read. I understand that “casebook” suggests a collection of materials and primary documents, but the analysis or examination of the cases is almost nonexistent. The overall effect here is a patchwork of wildly varying stories with sometimes a thin thread connecting them. Just when Vallée presents a possible interesting case, he jumps to another one that only connects very loosely. Halfway through, I was occasionally intrigued by certain cases, but ultimately left needing more hard evidence and/or analysis of the cases. Rather than coming to accept Vallée’s assertion that UFO encounters and abductions – from beings living in a universe parallel to our own – have been occurring throughout history under various guises (fairies, trolls, gods, etc.), one might just as well equally conclude that UFO encounters are the modern equivalent to fairy tales and urban legends – fictional fantasies and imaginative retellings of natural events as supernatural stories. Coming from someone who “wants to believe,” this is pretty much the opposite of what Vallée’s intentions were in writing this book, I’m sure. By the time he brought up obvious frauds like Joseph Smith and Uri Gellar, he had almost lost me.

But the last third of the book suddenly shifts. He moves away from the “casebook” and describes the Famita and Lourdes events (which are genuinely fascinating) in great detail, and then presents his hypothesis that UFOs are interdimensional. This is where the book excels, and I only wish he had dispensed with the long string of cases and just focused on these ideas.

The final section is where Vallée finally piqued my interest, with a discussion of UFOs as potentially physical manifestations of interdimensional beings acting as a planetary regulation function (think the Gaia theory and the positive/negative feedback loops that regulate complex systems, although that is not directly mentioned by Vallée), or perhaps a physical manifestation of the human unconscious (or collective unconscious) that symbolically communicates with humans by shaping our beliefs and guiding our evolution – the idea of myth as being a kind of dream-state that reveals a dimension beyond the fourth that is just not fully understood. Sort of like Jung meets string theory (both of which are touched on by Vallée) with a hint of 2001: A Space Odyssey.

This is fascinating to think about as a speculation for a whole host of human eccentricities that can't be either confirmed or debunked. The final 30 pages of the book really save it from being nothing more than a long string (pardon the pun) of old stories, mixed in with frauds and hoaxes. I understand that the casebook section was intended to bolster his conclusions, but by including so many obvious frauds – Uri Gellar! Mormons! – he muddied the waters, so to speak. Even so, the final section made this a worthwhile read, if one has an open mind and can get beyond some of the “absurdity” that Vallée honestly admits, and even claims is part of the entire UFO phenomenon.
Profile Image for Hank.
42 reviews4 followers
September 6, 2022
It seems like every UFO researcher has their own opinion of the true origin and nature of the phenomenon. Weirdly, the ones who are the least biased, take the most information into account, and have the most impressive scientific or achademic credentials, always seem to form the most surreal and mind blowing opinions. In the case of Jacques Vallee, he meticulously lays out a compelling case that whatever UFO's are, they seem to be the same phenomena that were taking the shape of fairy folk & gnomes in officially documented European cases hundreds of years ago, angels, demons, and gods from millenia before, and they share uncanny traits and patterns with other myths and folklore from cultures around the world throughout the history of record and legend. These constant patterns and identical narratives, he proposes, suggests that they likely are not only a real phenomenon, but are not likely to be strictly physical extraterestrial entities from a distant star, but that this interpretation of them is yet another misdirection by them about their true nature, meant, perhaps to generate new folklore and religions that are more compatible with our current level of scientific knowledge. He then theorizes that perhaps what they actually are is some kind of multidimensional phenomena that has a vested interest in exerting long term influence on human culture for unknown reasons. He doesn't claim to have any strong opinions about whether the phenomena is automatic like a very sophisticated machine, an actual species with its own civilization coexisting with our own in another phase of reality, or even if it's some kind of psychokinetic effect of the human unconscious that we unknowingly generate ourselves, and cause to materialize collectively as an evolved survival mechanism that helps to prevent our whole civilization from destroying itself through war or hopelessness. But he definitely does not believe that they are mechanical spacecraft. His decades of analysis of thousands of cases has convinced him that the extraterrestrial explanation is not weird enough to explain the evidence. Much like Charles Fort and John Keel, Vallee is unable examine the data objectively without concluding that what ever is causing it is so beyond our understanding of physics that the methods necessary to understand it fully likely haven't even been invented yet.
Profile Image for Ani Møller.
18 reviews3 followers
June 17, 2023
A great book to start with if you’re interested in UFOs.

He collates contact/sightings from across human history. From ancient myths to cave art to religion to folklore to todays UFO themes. Utterly fascinating, and presented in a way that you’d expect from an author who is also an astrophysicist and computer scientist.

One of the most interesting books I think I’ve ever read!
Profile Image for Greg Williams.
231 reviews5 followers
July 30, 2022
The author of this book, Jacques Vallee, has been involved in investigation of UFO encounters since the 1960’s. In this book, he provides a sampling of human encounters with “alien beings” throughout history. He provides examples from the Bible and other ancient history, medieval history, and modern times. And he argues against the idea that UFOs are spacecraft from outer space.

He writes:

I have carefully kept my distance from the very vocal groups of researchers who claim that UFOs are interplanetary visitors; such a conclusion is not only premature but is contradicted by several basic facts that become apparent only when one takes a historical perspective of the field rather than studying a single case at a time and trying to generalize from isolated events.


In this case, he lays out his case that the alien encounters throughout history (e.g. angels, fairies, elves, UFO pilots) are all manifestations of the same thing, expressed in different ways based on the culture at the time.

Let us start with a simple fact: man has always been aware that he is not alone. All the traditions of mankind carefully preserve accounts of contact with other forms of life and intelligence beyond the animal realm. Even more significantly, they claim that we are surrounded with spiritual entities that can manifest physically in ways that we don’t understand.

Based on that starting point:

The UFO occupants, like the elves of old, are not extraterrestrials. They are the denizens of another reality.


His understanding of what these encounters might represent is based on "the psychic effects it produces (or the psychic awareness it makes possible) in its observers." He views UFO encounters as psychic or spiritual encounters. At one point, he calls them a “spiritual control system” from a part of reality that we don’t understand. He even speculates that their purpose may be “long-term social manipulation.”

What we see here is not an alien invasion. It is a spiritual system that acts on humans and uses humans.


I found this to be a fun read. It was interesting to read eyewitness accounts of alien encounters across a broad range of history. I like the fact that he doesn’t assume that the witnesses of alien encounters are crazy but instead treats them with dignity by accepting their testimony as a real experience that we just don’t understand. And I found his view of UFOs to be interesting and worthy of consideration.

All in all, I liked this book and would recommend to anyone with an interest in UFOs or other paranormal phenomena.
Profile Image for Rinstinkt.
220 reviews
November 8, 2023
Excellent book.

A must read for anyone who has a curiosity about the topic of UFOs/UAPs.
Vallee argues that what some people perceive as UFOs/UAPs are modern reiterations of an old and ever present phenomenon that in the past manifested as angels, demons, fairies, elfs etc.

That there seems to be intelligence behind the phenomenon, and that these manifestations act like a control mechanism of some sort, psychic, religious, philosophical.

Vallee leaves lots of breadcrumbs in regard to other aspects of the UFOs: government and occult involvement. Again, repeating what he has written in Messengers of Deception: UFO Contacts and Cults he mentions A. Crowley, J.W. Parsons, L.Ron Hubbard, William Dudley Pelley, George Hunt Williamson etc.

Valle also briefly brings up physics by proposing that information and consciousness might be closely related to the phenomenon that generates what people describe as UFO/UAP


A short quote from toward the end of the book:

There is a strange urge in my mind: I would like to stop behaving as if I am a rat pressing levers – even if I have to give up the cheese and go hungry for a while. I would like to step outside the conditioning maze and see what makes it tick. I wonder what I would find. Perhaps a terrible superhuman monstrosity the very contemplation of which would make a person insane? Perhaps a solemn gathering of sages? Or the maddening simplicity of unattended clockwork?
Profile Image for Jonathan Hockey.
Author 2 books25 followers
October 14, 2021
A worthwhile read full of interesting contact stories and well considered intelligent explanations for them. The craft may not merely be the presumed "nuts and bolts" technology of an alien civilisation from a distant planet. In fact they may not be this at all. They may be a merely mythical guide to our future spiritual evolution, a sign of yearning for a lost contact with a more deeper purposeful sense of reality, or they may be interdimensional informational contacts that transcend our typical physical block world of space and time in ways we find hard to express being stuck within the conceptual prison of this structure of thought.

The metaphor I find most resonant in this work is this idea of the contact and alien phenomenon as like a thermostatic valve controlling and balancing the spiritual and consciousness level of humanity, between fear and trust, love and hate, ensuring that we continue on a healthy path, connected to, and respecting, a surrounding reality always slightly beyond our full rational grip, instead of being disconnected from it in some of the ways modern science has unfortunately prescribed for us.
447 reviews2 followers
December 31, 2021
Similar to his other works, Jacque Vallée espouses his theory that UFOs, spirits, fairies, dwarves, etc are all the same phenomena. His clear and logical format is free from the sensationalism found in other books on the subject. The modern iteration of whatever the underlying thing is, masquerades as extraterrestrial visitors to earth. He comes to the conclusion that this can’t be true as the supposed ET encounters are too frequent and too weird to actually be ETs. Coverups are due to people not wanting to be ridiculed and governments not wanting to admit their ignorance. To him, the only explanation can be that these are physical objects/creatures from another dimension that have been here as long as humanity. Their visits must have some sort of meta-logic, influencing society and culture through its absurd encounters. The destination and purpose are unknown. Reading this 33 years after it was written, his description of the state of study of UFOs hasn’t developed much. The dominant theory is still either they are the result of hoaxes/misidentifications/mental illness or aliens from another planet.
Profile Image for Polly.
58 reviews
March 31, 2022
This is by far my favourite theory seeking to explain the "UFO/alien phenomenon". Jacques Vallee's writing style isn't always the nicest to read, but his arguments are succinct and well-researched and they really do make a lot of sense when put all together. It is so refreshing to read a serious work that attempts to explain this phenomenon as something OTHER THAN extraterrestrial WITHOUT dismissing it. I thought it was fantastic.

The alien/UFO mystery has always intrigued me, but it's kind of boring reading the same old theories rehashed again and again. I also am extremely skeptical when reading such books (even though I do enjoy the topic greatly). Jacques Vallee does a great job of tearing down the extraterrestrial hypothesis while ALSO providing a comprehensible explanation for what might really be going on. God, this was refreshing!

...but what I loved most about this work was his deep exploration into centuries-old folklore, unravelling stories about "fairies" and other strange "beings" that humans have constantly encountered throughout history. It was so fascinating. I will definitely read this book again. Really excellent work!
Profile Image for Dollie.
1,351 reviews38 followers
January 8, 2021
I have been fascinated by UFOs since I was six years old, a very long time. After watching The UFO Incident in 1975 and then learning whatever I could about Betty and Barney Hill’s encounter, I’ve always believed their story was true. Then I started reading about other encounters and believed some of them, as well. I didn’t know I still had any UFO books, but when I recently found this one in a box of books, even though it’s dated, I knew it would be good reading and it was. Dr. Vallee is one of the world’s UFO experts (he was portrayed in Close Encounters of the Third Kind by Francois Truffaut). This entire book is about UFO encounters, some I’d never heard of and some of which happened hundreds, even thousands of years ago. Dr. Vallee suspects that “aliens” have always been here and that they don’t come from outer space, but from a different dimension right here on Earth. A dimension which humans haven’t had the knowledge to figure out yet. Perhaps he’s right. I may never know, but reading this made me want to find more recent books on the topic.
3 reviews
April 6, 2021
Helped clear up a few misconceptions I've had with this whole phenomenon.

I feel Jaques is on the right path. It is hard to make sense out of all of this but it is good to constantly question everything and not get caught up in a particular mindset. I think the lesson here is to realise that you actually know nothing and nothing is as it seems. Perhaps thanks to Jaques and others this will change. What is this universe and where did it come from? This is the only question I have. Nobody knows and anyone who claims to have the answers is immediately in the bin. Jaques does not claim to have all the answers. Every answer only raises more questions and there are good questions here.
Profile Image for Bryan .
561 reviews
June 15, 2025
I just finished my second read through. I absolutely loved this book. It instantly topped the charts for me on being one of the best books, dare I say, the best book, on the subject. After having read so much about the mystery, I have more or less come to the same conclusion as the author. His wisdom, experience, and educational background make him uniquely positioned to be the foremost living expert in the study of these phenomena. I am so excited this is only the first of three books and now that I have purchased the next two volumes I will immediately start reading the second book in the series. I highly recommend Dimensions if you are interested in the subject. It is very grounded and humbling.
Profile Image for Richard Tubb.
Author 5 books30 followers
December 17, 2023
This is an incredible book from noted Scientist and UFO expert, Jacques Valles.

As well as presenting some amazing UFO sightings and encounters, Valles offers some very interesting hypothesis on what exactly these nuts and bolts ships and their occupants represent.

Visitors from other parts of the galaxy, or perhaps inhabitants of other dimensions? What if the history of UFOs is actually some sort of control system for the evolution of our planet?

As always, Valles writing is engaging and really thought provoking. Highly recommended if you want to go beyond the traditional UFO concept of “visitors from outer space”.
6 reviews3 followers
October 22, 2009
In DIMENSIONS, the first volume of a trilogy, Dr. Jacques Vallee reexamines the historical record that led to the modern UFO phenomenon and to the belief in alien contact. He then tackles the enigma of abduction reports, which come from various times and various countries, as well as the psychic and spiritual components of the contact experience. In the last portion of the book, he notes the factors that inhibit research into the phenomenon--the triple coverup and political motivations--and concludes that the extraterrestrial theory is simply not strange enough to explain the facts.
Profile Image for Kevin W. Carr Carr.
23 reviews
August 4, 2020
A new perspective

I read a bit about Mr. Vallee's writing recently and decided to check out his well researched theories on the UFO phenomenon. I'm very impressed. I won't divulge the pertinent information, however I say this is a serious alternate perspective. This has provided a new avenue to re-see all the massive amounts of data trickled out over the years. If you wish to be given fresh concepts to a issue that seems to be being revised and revisited recently, this will be healthy food for thought.
Profile Image for MR GUY R EDMONDSON.
1 review
August 17, 2020
A good overview and analysis of the historical information

Easy to read and a cautious threading of an alternative view which fits the current state of play regarding what we can make of our apparent recent moves towards ‘disclosure’ - Vallee provides a useful platform of sceptical openness and invites the interested reader to question received suggestions that aliens are extraterrestrial- 5 star stuff!
Profile Image for Christine Best.
247 reviews1 follower
September 25, 2022
An early rebuttal of the idea that UFOs are extraterrestrial and along with John Keel’s ‘Operation Trojan Horse’ absolutely essential reading for anyone wanting to place the phenomenon in a larger context. These books seem to be gaining in popularity again recently especially now UFOS are being increasingly connected with other paranormal and psychic events.
Profile Image for Gary Perez.
28 reviews
February 24, 2016
This was definitely a good read highly recommend it to anybody that enjoys reading about the UFO phenomenon. I specifically like how the author presents an alternative theory as to the origin of extraterrestrials. It was very different from other things I've read and very thought-provoking.
2 reviews1 follower
March 20, 2017
excellent logical analysis of the alien contacts and quite a plausible premise. i will be reading more of his future books as this is a nasa scientist who worked on the precursor to the internet (arpanet).
36 reviews1 follower
August 13, 2020
Jacques really engages the reader. Although he
seems to believe that the visitors do so as
interdimensionals, how they regulate their
display frequencies to do so is not thoroughly
explained. In all fairness, I haven't found
an author able to do that. yet.
23 reviews
May 13, 2024
High Value Data

The author exceeds Sagan, exponentially. Now forge ahead with integrating the dual energy concept! This book represents high value to readers and researchers in completing humanity's existential puzzle.
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