"I know that all beneath the moon decays"

I know that all beneath the moon decays,
And what by mortals in this world is brought,
In Time’s great periods shall return to nought;
That fairest states have fatal nights and days;
I know how all the Muse’s heavenly lays,
With toil of spright which are so dearly bought,
As idle sounds of few or none are sought,
And that nought lighter is than airy praise.
I know frail beauty like the purple flower,
To which one morn oft birth and death affords;
That love a jarring is of minds’ accords,
Where sense and will invassal reason’s power:
Know what I list, this all can not me move,
But that, O me! I both must write and love.