Comment by pdonis

> unlike the caricature seen in the movies

I agree that the movie portrayal was totally unlike the Denethor in the books.

> He knows Sauron is trying to manipulate him

To some extent, yes. But I'm not sure he fully realizes what's going on. For example, he sees the fleet with black sails coming up Anduin--but he didn't see any of the events that led to that fleet being taken over by Aragorn and his followers? He could have.

> because his claim is weaker than Aragorn's

I don't think this is given as a cause of Denethor's doom in the books.

> because he keeps using it repeatedly over the decades

This is mentioned in the books, yes.