(IANAL) Not sure about 'permission' and your legal geography, Tilly, (California?) but I'd be pretty surprised if even quoting all 256 in the context of a critique didn't fall easily under "fair use" provisions of US copyright law. From the link above (my emphasis):
The 1961 Report of the Register of Copyrights on the General Revision of the U.S. Copyright Law cites examples of activities that courts have regarded as fair use: “quotation of excerpts in a review or criticism for purposes of illustration or comment; quotation of short passages in a scholarly or technical work, for illustration or clarification of the author’s observations; use in a parody of some of the content of the work parodied; summary of an address or article, with brief quotations, in a news report; reproduction by a library of a portion of a work to replace part of a damaged copy; reproduction by a teacher or student of a small part of a work to illustrate a lesson; reproduction of a work in legislative or judicial proceedings or reports; incidental and fortuitous reproduction, in a newsreel or broadcast, of a work located in the scene of an event being reported.”
So, make it critical, scholarly, and a parody, and you should be on safe ground, regardless of what O'Reilly's lawyers say. (If you can afford the legal costs of a defense, of course...)
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