Unpacking an Enigma

Dennis Ritchie with nephew Sam Ritchie

In many ways the story of Dennis Ritchie’s doctoral thesis is a metaphor for his life story… groundbreaking, transcendent, shrouded in mystery.

David Brock published an article on The Computer History Museum website in June 2020 that told the story of Dennis Ritchie’s Harvard doctoral thesis.  Dennis never submitted it.  Something happened, and then all mention of it just disappeared for 54 years until 2012, a year after Dennis died.  And, as Brock reports, the concepts Dennis described in his dissertation represented breakthrough thinking in computer theory and were historically important.  On that basis alone, it’s a shame his thesis never saw the light of day.

Now that the thesis has been found and is available by PDF, the next question becomes… what happened? Brock settles on a story featuring a dispute over a library fee. Somehow, while sufficient this explanation doesn’t quite seem satisfactory.

This website is dedicated to learning more about Dennis Ritchie’s dissertation.
There are three main unsolved questions…

  • Dennis was due to graduate in February 1968, all signs were pointing to his successfully attaining his PhD at that time, he had a complete thesis draft with only a half dozen insignificant typos identified by him as still needing correction. And then he didn’t graduate, never got a PhD. And then he took he took his typed thesis document and put it on the shelf, where it stayed until after his death. What happened? Maybe it was as simple as a dispute over fees, maybe underlying was something more consequential. Memories have faded, likely we will not get a definitive answer at this point.
  • The DMR thesis, draft copies of which have now been found, represents what is typographically one of the most sophisticated math dissertations of the 1960s, perfect placement of sub/superscripts and abundance of Greek letters and math symbols, and the uniformity from version to version. Did he hire the best professional typist in Cambridge to help create such a close-to-perfect document? Or could he have somehow tapped into new technologies that would allow him to do things that other students couldn’t do? Experts are clear that computers were not advanced enough to have been able to aid Dennis in January 1968. Other experts are clear that the dissertation draft document could not have been typed by hand, the typography is too uniform and too perfect. There has to be an answer, but we have not found it yet.

  • Over the course of his life Dennis won the most prestigious awards and was given countless honors and accolades.  With few exceptions he was referred to as “Doctor Ritchie” and listed as having earned a PhD from Harvard in 1967 or 1968. How is it possible that nobody seems to have known the true status, that Dennis had never been awarded a doctorate and was formally “Mr. Ritchie” not “Dr. Ritchie”? This is emerging as a live question, there is more to be learned and we will be pursuing this further.

This has been, and continues to be, a fun and rewarding research project.   Along the way we’ve realized that we have quite a trove of personal material about Dennis in our family archives, these materials on their own provide a window into Dennis’ life and are worth sharing for the sake of understanding him better.  We’ve organized these in the ARTIFACTS section. 

Maybe the answers will become clear, maybe we’ll never know… but these were historic times and the DMR thesis is historic itself, capturing more of what we can learn about all this is proving to be worthy in itself. 

Amazing is that more than 50 years, with all the right people now examining closely, the story of the thesis remains an enigma.  These should not be hard questions, given that Dennis is so famous.  But not so.  Dennis’s siblings don’t know what happened, with one exception he never talked about it to us. None of his Bell Labs colleagues seem to know.    

So this website is dedicated to learning about Dennis Ritchie’s doctoral thesis and about the intellectual, social and cultural background environment during his graduate school and early Bell Labs years, 1964-1968. We are sharing the information/evidence/observations/opinions we find here.

We periodically update this website, please keep checking back for new revelations!

Dmrthesis.net is managed and run by the Ritchie family. 
Thanks for joining us!