It is only by being in trouble that people can understand how far from easy it is to be the master of one's feelings and thoughts.
 Anton Chekhov, A Misfortune (1886). copy citation

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Author Anton Chekhov
Source A Misfortune
Topic understanding feelings
Date 1886
Language English
Reference
Note Translated by Constance Garnett
Weblink https://en.wikisource.org/wiki/A_Misfortune_(Chekhov/Garnett)

Context

“But when Andrey Ilyitch arrived soon afterwards she hardly greeted him. The rush of false feeling had already passed off without proving anything to her, only irritating and exasperating her by its falsity. She was sitting by the window, feeling miserable and cross. It is only by being in trouble that people can understand how far from easy it is to be the master of one's feelings and thoughts. Sofya Petrovna said afterwards that there was a tangle within her which it was as difficult to unravel as to count a flock of sparrows rapidly flying by. From the fact that she was not overjoyed to see her husband, that she did not like his manner at dinner, she concluded all of a sudden that she was beginning to hate her husband” source