During the early 1960s, Dijkstra and Naur were much in sync with each other's research aspirations. They were, after all, both involved in implementing and promoting the ALGOL60 programming language. Dijkstra's 1970 `Notes on Structured Programming' was a pivotal point in their relationship, as described in my interview with Naur. From that point onwards, their research agendas diverged.
By November 1981, Dijkstra had become interested in mathematical methodology; he wanted to find an objective measure for simplicity, for ``mathematical elegance''. In his words:
I have come to the opinion that some arguments are objectively simpler than others. [...]
[A]mong a great number of mathematical colleagues I found a much greater consensus about what was really elegant than they had suspected. [EWD803, p.4]
Naur, by contrast, believed a researcher should respect the multitude of personal styles in solving problems. Naur opposed those who claimed that there is one uniform way to conduct science, nor did he believe that the notion of ``mathematical elegance'' can be agreed upon, let alone be defined and measured.
The deeper difference between Dijkstra and Naur lies in the former's implicit acceptance and the latter's explicit rejection of Western philosophy. According to Naur, Dijkstra viewed mathematics and science as the only vehicles for true progress. But for Naur ``scientists'' are merely symbol chauvinists who firmly believe that mathematical structures prevail over material ones.
In November 1981, Dijkstra had just commenced with his quest:
For the time being it suffices to capture mathematical elegance by the slogan ``short is beautiful''. [EWD803, p.4]