Philo Judaeus De Plantatione 167

[167] And besides all this, we must likewise add, that we are not speaking of a stern-looking and sordid kind of wisdom, contracted by profound thought and ill-humour; but, on the other hand, of that wisdom which wears a tranquil and cheerful appearance, being full of joy and happiness, by which men have often been led on to sport and divert themselves in no inelegant manner, indulging in amusements suitable to their dignified and earnest character, just as in a well-tuned lyre one may have a combination uniting, by means of opposite sounds, in one melodious harmony.