Non è male alcuno nelle cose umane che non abbia congiunto seco qualche bene. - Francesco Guicciardini

If displeased with any man, do all you can to prevent his seeing it, for otherwise he will become estranged. And occasions often arise when he might and would have served you had you not lost him by showing your dislike. Of this I have had experience to my own profit. For once and again I have felt ill-disposed towards some one who not being aware of my hostility has afterwards helped me when I needed help and proved my good friend.

There is no evil in human affairs that has not some good mingled with it.

Gli ambasciadori sono l'occhio e l'orecchio degli stati.