From Taoist tradition.
One day, the wise sage Zhuangzi was fishing when a prince paid him a visit to offer him the illustrious position of “supreme chancellor” in his father's kingdom.
Zhuangzi quietly fished on and, without turning around, said:
“I heard that there is a most sacred tortoise, which has been dead for almost three thousand years. The king keeps this tortoise packed up in a beautifully crafted box on the altar in his ancestral shrine.”
“Now,” Zhuangzi continued, “do you think that tortoise would rather be dead and have its remains honoured like this or be alive and wagging its tail in the mud?”
The prince answered that, of course, it would rather be alive and wagging its tail in the mud.
To which Zhuangzi replied, “Well then, leave! I, too, prefer to remain here—free, unbound and independent—wagging my tail in the mud.”
To the Stoics, living a good life doesn't necessarily involve acquiring high office or great wealth and power. Oftentimes, being wealthy and powerful just means you are beset by a whole new set of problems. Freedom and independence means not being tethered to these things.
Rather than striving for mastery of external things, it is more important to master oneself in the quest for actual liberation. As Epictetus—who was once a slave—said, “no man is free who is not a master of himself.”
Once you've mastered yourself, it makes no difference whether you are wagging your tale in the mud like Zhuangzi's tortoise or fabulously wealthy like the Roman statesman and Stoic Seneca—for you will already be free and won't be so easily influenced and swayed by external circumstances, people and objects.
As author Stephen Batchelor explains, instead of external gain—the realm of having, focus on internal tranquility and happiness—the realm of being.