The aim of this essay is to provide a big-picture canvas of the wider meanings of the Left-Right dimension in human thinking and personality. It's a dimension that precedes and transcends politics, but may well explain some of the puzzles about the political Left and Right. I begin by discussing general findings on the cross-cultural differences in the thinking and attitudes of Leftists and Rightists on many different aspects of life. Then I describe how this dimension has manifested itself in language, and how it became part of politics during the French Revolution. Then I show how the left-right dimension manifests itself in personality, and that political preferences do relate to this dimension.

After showing the considerable difference between the political Left and Right in personality and social attitudes, I suggest that they nonetheless share certain essential similarities that are relatively rare in the general population, especially a high degree of moral fervor and moral anger, even while they differ completely on what they are fervent and angry about. My next step is to suggest that this shared moral fervor leads political Leftists and Rightists to have similar condescending attitudes towards their more moderate left-oriented or right-oriented compatriots, those who are merely "liberal" or only moderately "conservative."

I conclude this document with a puzzle. Both Leftists and Rightists end up working in various hierarchical, top-down organizations. That fact seems fairly straightforward and understandable for the Rightists because they believe in hierarchy, as will be shown. But how do Leftists, who are egalitarian in their values, often end up in very hierarchal organizations? It's at this point that we have to look to social psychology and sociology for answers.