What Seneca can teach us is fidelity to ourselves - to God within us - and kindness towards our fellow human beings:
© (Versión Alemán) Karl O. Schmidt, Drei Eichen Verlag, Engelberg / Schweiz
»Wisdom teaches to worship the divine and love the human. Continuing goodness overcomes evil. --- In order to stay the same in the alternation of happiness and misfortune, to learn from all and to gain wisdom, and often withdraw back into yourself. The object of your strivings should be to become a living image of God, and to obey more the inner voice than follow the lure of things. Make an account of yourself daily, and make sure your striving is always good. Good is what makes you better and more efficient and makes the people around you happier. Whoever lives like this, becomes the master of things and destinies.«
Rudolf Eucken, the philosopher of culture, notes in his work "Die Weltanschauung der großen Denker" that the Stoics have done an incomparably great deal for solving the problem of life, especially through the scientific foundation of ethics:
»Man is a member of the world, which is a realm of reason, a system of meaningful order and strict interconnection. Through his nature he is able to grasp the All-Reason. He can behave in two ways: he can, without his own impulse, let happen what is going on in the world, or seize the idea of the world, and see its necessities, and thus transform it into freedom ...
Here is the point of your own decision: whether that, what must happen, happens without and against him or with his consent. This alters completely the character of his life, which makes him either a slave or the master of things.«
The idea of the world-reason, however, -- according to Euken -- can only grant freedom and happiness when our whole being is transformed into thought, and everything is removed from it, which subordinates us to alien powers. This, however, do the feelings with his affects, by entangling us in the sorrows and sufferings of existence -- especially by misjudging things. Because the sufferings as well as the external existence have power only over the person, who gives them reality through his own thinking, as the Stoic teaches: "It is not things that disturb us, but our opinions on things".
Thus the thinking becomes action, a think-action, the wisdom and the virtue are merged into one. Only this think-action offers real happiness. But the severity of the task did not escape the Stoics. For them, live is struggle -- against the wrong assessment of things and the dangers of one's own nature.«
(English traduction by Jörn Malek)