Various excerpts from the wikipedia article on The Art of the Deal:
[Tony] Schwartz called ghost-writing the book his "greatest regret in life, without question," and both he and the book's publisher, Howard Kaminsky, alleged that Trump had played no role in its writing.
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Trump and Schwartz had an agreement to split royalties from the sale of the book on a 50–50 basis. In 1988, Trump set up the Donald J. Trump Foundation to give away the royalties, promising four or five million dollars "to the homeless, to Vietnam veterans, for AIDS, multiple sclerosis". According to a Washington Post investigation the donations failed to materialize; the paper said "he gave less to those causes than he did to his older daughter's ballet school".
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Schwartz described Trump's lying:
'Lying is second nature to him,' Schwartz said. 'More than anyone else I have ever met, Trump has the ability to convince himself that whatever he is saying at any given moment is true, or sort of true, or at least ought to be true.'
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As biographer Gwenda Blair wrote in 2000, "In The Art of the Deal, [Trump] claims that business deals are what distinguish him ... but his most original creation is the continuous self-inflation." Still, those tracing out Trump's life could not discern the more limited reality all at once. Speaking 20 years later, Blair bemoaned her failure, as a biographer, to have "understood how fabricated [the book] was ... how that founding myth was so riddled with at best exaggeration."
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Based on Trump's tax returns between 1985 and 1994 which showed a loss greater than "nearly any other individual American taxpayer" during that period, co-author Schwartz suggested that the book might be "recategorized as fiction".
