Brook's Lear

It's a truism to say that Peter Brook's film King Lear is a masterpiece. But what is a masterpiece? Saying this of a work can be a way of not looking at it: the artwork becomes "timeless", a glazed exhibit in the museum of our cultural self-regard. It turns into a monument.Thinking this over after watching Brook's film recently, it seems to me that when I say something is a masterpiece, I mean