Rookies blame others. Learners blame themselves. Masters blame no one.

Epictetus, Enchiridion 5

The source

"Rookies blame others. Learners blame themselves. Masters blame no one." Epictetus said it in Enchiridion 5. Translated by George Long, 1877.

"It is the act of an ill-instructed man to blame others ... of one who has begun to be instructed, to lay the blame on himself; and of one whose instruction is completed, neither to blame another, nor himself"

George Long, 1877, Enchiridion 5.

Who said it

Epictetus (c. 50–135 AD). Born enslaved, became the most influential Stoic teacher of his age. His student Arrian wrote down the Discourses and the Enchiridion.

Questions

Who said "Rookies blame others. Learners blame themselves. Masters blame no one."?: Epictetus (c. 50–135 AD). Source: Enchiridion 5.
What is the original wording?: It is the act of an ill-instructed man to blame others ... of one who has begun to be instructed, to lay the blame on himself; and of one whose instruction is completed, neither to blame another, nor himself (George Long, 1877). Translated by George Long, 1877.