Can you copyright "Ideas"?

This is a crazy law suit! It says that the idea fromthis 1982 book was copied.. so is there a copyright for an IDEA??

The author of The Da Vinci Code “lifted the central theme” of the bestselling novel from a non-fiction book about Jesus and the Catholic Church, the high court was told today.

Writers Michael Baigent and Richard Leigh are claiming that the American novelist Dan Brown appropriated themes and ideas they explored in their 1982 book The Holy Blood and the Holy Grail

They are suing their own publishers, Random House, which is also Mr Brown’s publisher, for breach of copyright in the potentially far-reaching case.

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