Abstract
In a case study, the mechanism of decomposition of diazonium ions in solution is discussed; the reasonable mechanism brought forward in 1940 was not refuted until 1973, in spite of experimental results published in 1952 that were not consistent with the proposed mechanism. A new mechanistic hypothesis, mentioned in the literature in 1973, was in contradiction to the paradigm that nitrogen molecules do not react with organic reagents in solution. After a psychologically explainable crisis the new hypothesis was tested experimentally and the paradigm mentioned was falsified for this case. In the analysis it is shown that Pop-perian logic was commingled with Kuhn’s cycle of normal science, crisis, and revolution, as well as with a psychological barrier. Joint investigations of modern problems by chemists and philosophers of science are encouraged because they may elucidate how progress in scientific discoveries takes place at the present time.