10 Unreadable Books and Texts That Truly Defy Comprehension

The term impossible is often casually used when discussing challenging reads. It’s a phrase that’s commonly applied to difficult classics, and a simple Google search for “books that are impossible to read” brings up such works. While some texts may be nearly unreadable, very few are actually beyond comprehension. Here are 10 books that are truly indecipherable (except, perhaps, by their authors themselves). Some are written in codes or ciphers that have yet to be deciphered, while others were intentionally created to remain forever unintelligible.

1. The Voynich Manuscript

The Voynich Manuscript is one of the most famous works written in an unknown script. Is it a fabricated or forgotten language? A cryptographic puzzle, or just an elaborate hoax? The truth remains elusive. What is certain is that the manuscript’s pages have been carbon-dated to the 15th century, and its earliest known owner was allegedly Emperor Rudolf II. The manuscript captured the public’s attention in 1912 when it was obtained by the book dealer Wilfrid M. Voynich, whose name is now forever linked to it.

In addition to the mysterious script, the manuscript is adorned with vibrant botanical illustrations. Some speculate that these could have been part of a reference guide, but the ambiguity of the plants depicted raises questions, as most of them cannot be definitively identified. To further mystify matters, the manuscript also contains drawings of celestial bodies and astrological symbols, and perhaps most intriguingly—images of naked women bathing in interlinked tubs filled with green liquid.

Despite numerous attempts to uncover the Voynich manuscript’s secrets, with theories ranging from it being a coded Hebrew text to the earliest known example of a proto-romance language, cryptographers remain skeptical. The manuscript is currently stored at Yale University’s Beinecke Rare Book and Manuscript Library, and has been digitized for public viewing.

2. The Rohonc Codex

Among the extensive collection bequeathed to the Hungarian Academy of Sciences by the noble Gusztáv Batthyány in 1838 was the enigmatic 448-page Rohonc Codex. Its origins remain a mystery, and its content continues to puzzle scholars. Some suggest that the alignment of the text with the right margin implies the symbols should be read from right to left. The codex also features almost cartoon-like illustrations, which, according to Benedek Láng, a professor at Budapest University of Technology and Economics, depict “Christ in a Gospel-like story.”

Much like the Voynich Manuscript, the nature of the Rohonc Codex remains uncertain. Whether it’s an undiscovered language, a cipher, or a deliberate hoax is still unknown. In 2018, two Hungarian researchers claimed to have cracked it, but in 2022, Chris Christensen, a mathematics professor at Northern Kentucky University, remarked that, “Their research suggests that the codex is breviary-like and largely consists of New Testament readings. However, some sections remain problematic, and some grammatical anomalies are unresolved.” Whether this represents the start of a breakthrough or another dead end is yet to be determined, but the text is available online for anyone keen to attempt deciphering it themselves.

3. The Beale Ciphers

In 1885, a pamphlet titled The Beale Papers was anonymously published. It tells the tale of Robert Moriss, who supposedly received the papers from a friend who had been entrusted with them by frontiersman and adventurer Thomas J. Beale. Inside the pamphlet were three ciphers that, once decoded, were said to reveal the location, contents, and heirs to Beale’s treasure. The pamphlet offers a solution to the second cipher (which, according to the author, uses the United States Declaration of Independence as the key), revealing the treasure as nearly 3000 pounds of gold, over 5000 pounds of silver, and a collection of jewels.

However, the other two ciphers remain unsolved, and attempts to locate the treasure in Bedford County, Virginia, where it is said to be hidden, have yielded no results (and no treasure). Efforts by the Beale Cipher Association, which was founded in 1969 and disbanded in 1999, as well as attempts by professional cryptanalysts and computer programs, have failed. This has led to speculation that the ciphers may be a hoax, yet the allure of the potential hidden fortune has kept the mystery alive.

4. The Ripley Scroll

Unlike many of the texts on this list, which are written in unknown languages or ciphers, the Ripley Scroll is readable as it was written in Latin and English. However, as Kay Sutton, Director of Medieval and Renaissance Manuscripts at Christie’s, pointed out, the Scroll is “expressed in rather obscure and archaic language.” This makes it difficult to fully grasp the meaning behind the Scroll, despite its legibility.

The Scroll seems to offer elaborate poetic instructions for creating the mystical Philosopher’s Stone, yet the process described is not only an unattainable feat but also shrouded in ambiguity. According to Anke Timmermann, a historian specializing in medieval and early modern alchemy, the relationship between the Scroll’s imagery and verses is “ambiguous and complex,” and she calls it “confused and confusing” in her work, Verse and Transmutation: A Corpus of Middle English Alchemical Poetry.

Currently, 23 versions of the Scroll exist, each with slight variations in imagery, color, and size. However, the origins of these Scrolls are shrouded in mystery. Although the Scroll is named after George Ripley, a 15th-century English alchemist, because his verses appear on it, there is no conclusive evidence that he was involved in its creation. Most of the known copies date from the 16th and 17th centuries, and it remains unclear who commissioned or created them, or the reason behind their creation.

So, can the words of the Ripley Scroll be read? Technically, yes. But do they make sense when placed in the context of the illustrations? Not really.

5. Ben Denzer’s 20 Slices of American Cheese

What defines a book? This is the very question that Ben Denzer sought to explore with his creation, 20 Slices of American Cheese. Rather than featuring printed words on paper, Denzer’s book is made up of 20 slices of Kraft cheese, each individually wrapped in plastic, and encased within a traditional hardback cover, which is bright yellow to match the cheese. While the book itself may not be legible beyond the cover and spine, it is housed in several libraries across the U.S. and at the University of Oxford. Thanks to the shelf stability of Kraft Singles, the book can be shelved like any other book, though it typically resides in a plastic container. However, with time, the cheese will inevitably expire, meaning that readers have a limited time to “read” it.

Denzer has expanded his food-inspired artistic approach beyond cheese with projects like 20 Slices of Meat (made of mortadella), 20 Sweeteners, and 5 Ketchups.

6. The Books in the Future Library Project

Located within the Silent Room of Oslo Public Library in Norway, there is an evolving collection of manuscripts that are not yet available for public reading. These belong to the Future Library Project, conceived by Scottish artist Katie Paterson in 2014. Every year, a new author is invited to contribute a book to the collection, and in 2114, the 100 completed manuscripts will be published, printed on paper made from a forest that is specifically planted for the project. Interestingly, many of the authors who will eventually participate in this endeavor have not yet been born.

Margaret Atwood became the first author to contribute to the Future Library Project, but apart from the title of her book, Scribbler Moon, the content remains a mystery. David Mitchell, who contributed From Me Flows What You Call Time, accidentally revealed one detail about his story: the lyrics from The Beatles' song Here Comes the Sun are included. By the time the book is published, these lyrics will be in the public domain, making them free of charge to use.

Paterson, the creator of the Future Library Project, will never read the works she helped inspire, and many of the authors will pass away before learning how their creations are received. While this comes with the natural frustration of unresolved curiosity for both authors and readers, the project encourages forward-thinking and offers a hopeful outlook for the future.

7. Xu Bing’s A Book from the Sky

Xu Bing’s work, Tiānshū (天书), or A Book from the Sky in English, was completed in 1991. It consists of four volumes filled with 4000 symbols that mimic Chinese characters but hold no meaning. The characters were designed to look as authentic as possible, and as Xu’s website states, 'The work simultaneously invites and denies the viewer’s desire to read the work.'

In a 1994 article for Public Culture, art historian Wu Hung argued that the English title of Xu’s piece does not fully capture the subtleties of the Chinese phrase. While tiān shū can refer to 'the mysterious divine canon of a religious sect,' it also colloquially means nonsense. Wu suggests that a more fitting title for Xu’s creation of nonsensical characters would be Nonsense Writing.

In 2003, Xu Bing began a project with the complete opposite intent: A Book from the Ground. This work is written in a visual language of universally recognized symbols, enabling anyone familiar with modern society to read it. The narrative traces the events of a day in the life of a typical office worker.

8. James Hampton’s St. James: The Book of the 7 Dispensation

When janitor James Hampton passed away in 1964, the landlord of his rented garage stumbled upon a large religious sculpture and a notebook filled with an undecipherable language. The artwork, named the Throne of the Third Heaven of the Nations’ Millennium General Assembly, was born from visions Hampton had of Christ’s return. Over the course of 14 years, he created the piece using salvaged materials. Items like cardboard, light bulbs, and jars were adorned with shiny metallic foil, forming an altar with a throne at its heart. Today, the sculpture resides at the Smithsonian, where it is celebrated as “America’s greatest work of visionary art.”

The notebook, titled St. James: The Book of the 7 Dispensation, remains an enigma. Professor Mark Stamp from San Jose State University, along with his student Ethan Le, tried to decode the text, known as “Hamptonese,” but their efforts were unsuccessful. They scanned the pages of the book and made them available online, but aside from a few English words like “REVELATION” that appear at the bottom of each page, the notebook appears to be filled with a random assortment of scribbles. However, after transcribing the text for digitization, Stamp and Le uncovered a discernible pattern.

“Of course, it’s entirely possible that despite its resemblance to language, Hamptonese might simply be the written equivalent of ‘speaking in tongues,’” the duo remarked in a 2005 paper [PDF]. If that’s the case, Hampton’s notes may remain unreadable even if his one-of-a-kind language is eventually cracked.

9. Luigi Serafini’s Codex Seraphinianus

Luigi Serafini’s Codex Seraphinianus, an encyclopedia created in 1981, is written in an entirely fictional language. While the script resembles Western writing systems, it has no actual meaning. The book is accompanied by bizarre, surreal illustrations—such as a group of surgeons in eccentric headgear applying human skin to skeletons, as well as psychedelic depictions of animals and plants. “I wanted my alphabet to give readers the same feeling children experience when they see books they can’t yet understand,” Serafini shared in a 2013 interview with WIRED. Despite efforts to decode the text, the author insists that “there is no meaning behind the script; it’s just a game.”

10. The Copiale Cipher

The Copiale Cipher, unlike the other ciphers and codes on this list, was cracked in 2011, and an English translation is now available [PDF]. Without this translation, however, the original remains unreadable. The 105-page manuscript, dating back to the mid-18th century, uses 90 different characters, including Roman and Greek letters, as well as abstract symbols [PDF]. Dr. Kevin Knight from the Information Sciences Institute at the University of Southern California teamed up with Beáta Megyesi and Christiane Schaefer from Uppsala University in Sweden to decipher the text. Using computers, they discovered that the original language was most likely German. The Roman characters weren’t meant to represent actual words, but rather to mark spaces between the abstract symbols, which, once decoded, revealed the hidden words. The Cipher itself describes the rituals of a German secret society called the Oculists, adding to its intriguing air of mystery.