The Wikipedia article offers some further interesting citations. https://en.wikipedia.org/wiki/Stupidity https://en.wikipedia.org/wiki/Stupidity James F. Well

The Wikipedia article offers some further interesting citations. https://en.wikipedia.org/wiki/Stupidity https://en.wikipedia.org/wiki/Stupidity James F. Welles, Understanding Stupidity "The term may be used to designate a mentality which is considered to be informed, deliberate and maladaptive." Welles distinguishes stupidity from ignorance; where stupidity means one must know they are acting in their own worst interest in that it must be a choice, not a forced act or accident. Lastly, it requires the activity to be maladaptive, in that it is in the worst interest of the actor, and specifically done to prevent adaption to new data or existing circumstances." = = = Otto Fenichel, "The Psychoanalytic Theory of Neurosis (London 1946)" "Every intellect begins to show weakness when affective motives are working against it". He suggests that "people become stupid ad hoc, that is, when they do not want to understand, where understanding would cause anxiety or guilt feeling, or would endanger an existing neurotic equilibrium."