In 1961, Dijkstra made an analogy between mathematical proofs and computer programs. After noting the analogy, he took aspects from the field of mathematics and projected them onto his own profession of programming.
Twenty years later, Dijkstra still stood by the analogy. This time, however, he projected the lessons he had learned from programming methodology back onto mathematics. Dijkstra was thus, in 1981, keen on defining a mathematical methodology. In Dijkstra's words: