Mistakes are their own instructors
Gold loves to make its way through guards, and breaks through barriers of stone more easily than the lightning's bolt.
One gains universal applause who mingles the useful with the agreeable, at once delighting and instructing the reader.
Desiring things widely different for their various tastes.
Be ever on your guard what you say of anybody and to whom.
He has carried every point, who has combined that which is useful with that which is agreeable.