David, the question is who determines whether a line like "Let us go then two by 
  two, double I and both of you" is a parody?

It doesn't satirize or mock the original, and I'm not sure whether it even comments on it. If lawyers have to determine what constitutes a parody literature is in trouble. Diana

Date: Wed, 26 Mar 2008 10:40:10 -0400
From: [log in to unmask]
Subject: Re: Copyright and TWL
To: [log in to unmask]

In a message dated 26/03/2008 13:47:35 GMT Standard Time, 
[log in to unmask] writes:
  this is a fascinating question! Heeding Nancy's warning, I'm toying with 
  paraphrasing some of Eliot's lines in my own poetry, but a bit of the original 
  is needed to clarify the allusion. I'm wondering how many words in succession 
  constitute a quotation. For example what if I write: "Let us go then two by 
  two, double I and both of you" is that liable to the charge of copyright 
The fine points of this law, especially when 
  considered for possible international application, are 

Mentioned here as regards US law:
In English copyright law there seems to be  precedent that ' 
a parody which is in itself 
original having its origin in the work parodied was held not to infringe the 
copyright in the work': Joy Music Ltd v Sunday Pictorial 
Newspaper (1920) Ltd  - a 1960 case.

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