Final answer:
Intellectual revolutions are driven by the progression of knowledge, societal demands, and the questioning of authority, such as during the Enlightenment and the American Revolution, showing their necessity in promoting societal progress.
Step-by-step explanation:
You asked why and how intellectual revolutions occur and whether we need another intellectual revolution. Intellectual revolutions often take place due to a confluence of factors, including the natural progression of knowledge, societal demands for change, and challenges to traditional authorities. For instance, after World War I, the questioning of elite authority and the interest in the psychology behind people's choices fueled contemporary intellectual history. During the Enlightenment, rational thought challenged religious tradition, paving the way for the Scientific Revolution's ordered and rational universe view, which in turn undermined the traditional Christian justification for societal hierarchies.
Further examination of history shows that ideological shifts, like those during the American Revolution, where ideas were found to precede revolutionary actions, illustrates that society often dictates when knowledge must evolve. And, as Enlightenment thinkers embraced the scientific method, shedding the light of reason on the world showed the potential to question and revise traditional ideas and institutions.