He's one of the most famous playwrights, directors, and as he puts it, former "brain-dead liberals" of our time.

David Mamet is a Pulitzer Prize winner, who for 30 years has championed liberal values. But in recent years, he's had a change of heart.

As an acclaimed playwright, screenwriter, film director and essayist, Mamet is best known for the films, "The Untouchables," "The Verdict," and "Wag the Dog."

He's also a part of the elite group of Pulitzer Prize winners, receiving the award for his play, "Glengarry Glen Ross."

For most of his highly successful career, Mamet has been a voice for liberalism. Now, the leading writer continues to speak out -- but not for the left.

Mamet has described himself as a former liberal who woke up, a man who realized that the mainstream media outlets he depended upon were biased and pushed a hypocritical worldview filled with flaws.

In 2008, he wrote a controversial op-ed for The Village Voice entitled, "Why I am no longer a 'Brain-Dead Liberal.'"

In the article, he methodically tears apart liberal beliefs.

Now, in his new book, The Secret Knowledge: On the Dismantling of American Culture, Mamet goes a lot deeper into his change of heart, taking on the key political and cultural issues of our times -- from taxes to religion to political correctness.

David Mamet spoke about what changed his mind and why on "The 700 Club," Monday, July 25.

--Published July 25, 2011.