Letters 85.19

But it is absurd to say that a man will be happy by virtue alone, and yet not absolutely happy. I cannot discover how that may be, since the happy life contains in itself a good that is perfect and cannot be excelled, If a man has this good, life is completely happy.

Now if the life of the gods contains nothing greater or better, and the happy life is divine, then there is no further height to which a man can be raised.

Seneca, Letters to Lucilius 85.19, translated by Richard Mott Gummere