Your enemy makes you wiser.
More Italian Proverbs:
The sound of the bell does not drive away rooks.Italian
How can the cat help it if the maid be a fool?
Italian
Where remedies are needed, sighing avails not.
Italian
There is never a cry of "Wolf!" but the wolf is in the district.
Italian
You will not be loved if you think of yourself alone.
Italian
Ever drunk, ever dry.
Italian