Insanity in individuals is something rare -- but in groups, parties, nations, and epochs it is the rule.

Summary

This quote suggests that while insanity may be uncommon in individuals, it is prevalent among larger social entities like groups, political parties, nations, and entire historical periods. It implies that the collective mindset of these larger entities often deviates from rationality or logic, leading to irrational behavior or decision-making. The quote highlights that the dynamics of groupthink and conformity can amplify and perpetuate madness in ways that are not typically observed on an individual level.