Arnold Kling believes that progressives, conservatives, and libertarians speak different languages. Their respective tongues derive from their tribes' animating myths.
The progressive myth is all about oppressors and the oppressed.
Progressives see themselves as standing up for groups that were historically oppressed. They see conservatives and libertarians as contributing to the evil of oppression, either overtly or through indifference.
Conservatives view the world in terms of civilization vs. barbarism:
Conservatives see themselves as standing up for the institutions and traditions that constrain man's barbarous instincts and preserve civilization. They see progressives and libertarians as contributing to the decline of civilization, either overtly or through indifference.
Libertarians are all about freedom vs. coercion:
Libertarians see themselves as standing up for voluntary transactions and individual choice, and they view all government interference as coercive. They see progressives and liberals as contributing to the expansion of government power at the expense of individual choice, either overtly or through indifference.
This tribal tongue-wagging means that our political commentary produces polarization rather than understanding. Kling's short ebook is available here