The post hoc ergo propter hoc defines attempts to establish cause-and-effect relationships where they do not exist, but there is a simple sequence of events unrelated to each other. This method was used, for example, in superstitions of ancient times, when the passage of a comet or a solar eclipse was associated with natural disasters. Probably, once these events coincided with some misfortunes, and, unable to explain the cause of the misfortune, people made a connection with a previous event – a comet or an eclipse. Nowadays, the post hoc ergo propter hoc manifests itself in politics, economics, and people’s everyday lives. For example, managers copy some external working conditions of successful companies and expect the same results, not caring about the professional growth of employees and creating conditions for effective work.
The method of the agreement involves observing several cases where a specific result is achieved and identifying factors or properties that occur in all cases. If two or more cases of the phenomenon under investigation converge in only one circumstance, then this circumstance is seen as the cause, or part of the cause, of the phenomenon under investigation (Hoffman et al., 2018). The logical mechanism of inductive inference by the method of agreement assumes several cognitive prerequisites. First of all, this method requires general knowledge of the possible causes of the phenomenon under study. Secondly, all circumstances not corresponding to the basic property of causality should be eliminated from the preceding ones. Thirdly, among the many preceding circumstances, recurring circumstances must be singled out. They would be seen as a probable cause of the phenomenon being studied. An example of the method of agreement is the fact that positive memory is associated with the presence of bright and colorful internal images.
Hoffman, R., Miller, T., Mueller, S. T., Klein, G., & Clancey, W. J. (2018). Explaining explanation, part 4: a deep dive on deep nets. IEEE Intelligent Systems, 33(3), 87-95.