Where do you see people tearing about...?

David Allen, from Performing Chekhov (2000):

Chekhov was opposed to the falsehoods and exaggerations of acting he saw in most theaters of his day. In a letter, he wrote:

where -- in streets and houses -- do you see people tearing about, leaping up and down, and clutching their heads? Suffering should be expressed as it is expressed in life -- i.e. not with your arms and legs, but by a tone of voice, or a glance; not by gesticulating, but by grace. Subtle inner feelings, natural in educated people, must be subtly expressed in external form. You will say -- stage conditions. But no conditions justify lies.

How, exactly, should 'subtle inner feelings' be 'subtly expressed in an external form'? Chekhov offered this advice to Olga Knipper on how to approach playing Masha in Three Sisters: 'Don't pull a sad face in any of the acts. Angry, yes, but not sad. People who have long carried grief within themselves and have become used to it just whistle and are frequently lost in thought.'