I wonder how many takes until they did this
The director leaves good actors alone to decide, and they themselves do not know what will happen
actors get into the character and try to do something that seems believable in the moment
Does this seem believable? If it does, then it is well acted
This makes for great acting. You don't know why it is great; it just is. But the reason Is you believed it.
That is why I like Jack Nicholson. He can do very interesting stuff without stepping out of character. Doing creative stuff without being real does not work, acting rewards creativity but only if it seems real.
That is my take
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