If you dozed off while your Western Civ prof was explaining the Investiture Controversy, Mike O'Hare can fill you in on why it still matters.
Bottom line: every form of government is improved by having loud, independent, critical voices, and no actual government really likes having them around. The claim to "speak truth to power" has something arrogant about it. But power does need to hear things, even things that aren't the Truth.
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