Unbound partners with AI platform for Cain's Jawbone challenge

Unbound is partnering with Zindi, an AI-platform company based in Africa, to challenge its AI’s machine to solve Cain’s Jawbone, a literary puzzle that became a best-selling TikTok sensation.

The crowdfunding publisher reprinted 70,000 copies of Edward Powys Mathers’ literary mystery, after it flew off the shelves last year. The book – a 100-page whodunnit in which six people die – can only be solved by the reader arranging the pages in the correct order. There is only one solution and, to date, only three people have ever solved it. The book has sold over 300,000 copies across all markets in the US, the publisher said. 

On the Zindi platform, participants can compete to reach the top of the leaderboard by having the highest percentage of accuracy. The accuracy is calculated by analysing initially 50 random pages of the book and the challengers’ inputted answers, and later, when the contest closes, the full 75 pages. 

Unbound plans to keep the resolution to the mystery private by only using a portion of the novel for the AI competition. As the competition closes on 31st December, participants have until then to resubmit their calculated answers to try and boost their scores, and ultimately win the competition.

In the new year, the top score will be awarded a prize of $300 (£244), encouraging users to move from the virtual event to testing their luck with the physical book. 

Amy Bray, Zindi data scientist and technical lead on the collaboration, said: “Natural Language Processing (NLP) dates back to the ’50s but most models such as BERT were trained on modern-day language. I am interested to see what techniques will be used on Cain’s Jawbone as the language is 100 years old.”

John Mitchinson, publisher and co-founder of Unbound said: “I wonder what Edwin Powys Mathers would make of the idea of solving his fiendish book-length puzzle using artificial intelligence? My hunch is that given his own freakish ability to spot literary patterns, he would have thoroughly approved."

The two companies were originally brought together by 25-year-old science and technology journalist Kenna Hughes-Castleberry. “I received Cain’s Jawbone from a friend and realized that it would be perfect to test with an AI,” Hughes-Castleberry stated. 

“I then began the hunt for AI companies willing to take the challenge on. It took about three or four months to find Zindi, after many of the big companies, like Amazon, Microsoft, and Facebook all said no. It was a strange request, to be fair, asking ‘can we borrow your AI technology for this challenge?’ But the possibility of seeing if AI could solve one of the biggest mysteries was too irresistible for a book lover and tech writer like me to pass up.”