Can actors be shy?

Excerpt from Sidney Lumet’s book “Making Movies”:

Paul Newman is an honorable man. He is also a very private man. We had worked together in television in the early fifties and done a brief scene together in a Martin Luther King documentary, so when we got together onThe Verdict, we were immediately comfortable with each other. At the end of two weeks of rehearsal, I had a run-through of the script … There were no major problems. In fact, it seemed quite good. But somehow it seemed rather flat. When we broke for the day I asked Paul to stay a moment. I told him that while things looked promising, we really hadn’t hit the emotional level we both knew was there in David Mamet’s screenplay. I said that his characterization was fine but hadn’t yet evolved into a living, breathing person. Was there a problem? Paul said that he didn’t have the lines memorized yet and that when he did, it would all flow better. I told him I didn’t think it was the lines. I said that there was a certain aspect of Frank Galvin’s character that was missing so far. I told him that I wouldn’t invade his privacy, but only he could choose whether or not to reveal that part of the character and therefore that aspect of himself. I couldn’t help him with the decision. We lived near each other and rode home together. The ride that evening was silent. Paul was thinking. On Monday, Paul came in to rehearsal and sparks flew. He was superb. His character and the picture took on life.

I know that decision to reveal the part of himself that the character required was painful for him. But he’s a dedicated actor as well as a dedicated man. And … yes, Paul is a shy man. And a wonderful actor. And race car driver. And gorgeous.