Matt’s History Is Never Past is a great post:
“The post-Civil War thinkers, pragmatists, believed that truth – objective truth – is a real notion, but that objective truth cannot be owned by any one person. It can only be owned by a social group, if at all. Diversity of perspectives, and real critical debate and discussion, led to the scientific method and the modern notion of science and academia. Right-wingers believe either that there is no such thing as truth, only interpretative variations that are a proxy for power, or that truth is held by atomized individuals or groups.
[. . .] Liberals are those who see the endpoint of a media system as a broad culture of tolerance, discussion, and argument leading to a socially higher truth. Reactionaries either want to limit participation to a small group of social liberals or conservatives, or the more extreme version of the them seek to remove the concept of truthfulness from discourse altogether.”