[A]lthough it might be difficult to see the logic in the Stoic’s definition of freedom as an acceptance of necessity, it is not difficult to understand the psychology behind it: the man who in a psychological sense is free knows no conflict of the will and has no choice; he, the wise man, does the one thing needed of him; like nature, he is ‘his own necessity.’  Therefore Seneca can write that: ‘It is actually the easiest thing in the world to live in harmony with nature; it is only the madness which we so commonly see around us that makes this difficult…’  This makes it the task of the individual to free himself from the many and to live—not according to accepted norms, but according to the law of nature. 

Villy Sørensen, Seneca: The Humanist at the Court of Nero