There is not unmitigated ill in the sharpest of this world's...

There is not unmitigated ill in the sharpest of this world's sorrows; I touch not the sore of thy guilt; but of human griefs I counsel thee, Cast off the weakness of regret, and gird thee to redeem thy loss: Thou has gained, in the furnace of affliction, self-knowledge, patience and humility, And these be as precious ore, that waiteth the skill of the coiner: Despise not the blessings of adversity, nor the gain thou hast earned so hardly, And now thou hast drained the bitter, take heed that thou lose not the sweet.