Harold Gotthelf, Professor of Satire wrote this entry on parody and satire in fair use, in response to my recent Slate  piece on Fair Use.

Satire is a purposeful art; it attempts to unmask folly that is posing as wisdom, or evil posing as good. Since false appearance is accepted as truth, satire must do something out of the ordinary to jar and upset the audience's vision of things.

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the real problem with the Court (in which it is only following a certain obtuse conventional idea) is in believing that satire is concerned with making only bitingly-negative (even vicious) attacks on society (what I have termed "the general").* This is reflected, I think, in the Court's statement that "society is lampooned" by satire. Thus, the Court has removed the specific (mild or harsh) attacks on a person's inadequacy of style, language, dramatic range, etc. from their rightful places in the universe of satirical means and modes.