The Most Intelligent Actor?
Truman Capote said, "The better the actor, the more stupid he is." He said this on Carson. I had a link to it on YouTube, but the video was removed. Too bad, it was hilarious! He gave examples.
I think Truman is largely right. An exception is Liev Schreiber. He's a fine, perhaps great actor, but read his quotes in his IMDB bio. Those are the most intelligent, insightful remarks I've ever read from an actor. No matter how rough a role Schreiber has, I think it's impossible for his intelligence not to break through. Because it's real. For that reason, I don't think he's very convincing playing stupid.