An amphiboly is a statement whose meaning is indeterminate in a peculiar way. The statement has an obvious meaning which is false and a hidden or concealed meaning which is true.
The story was told in ancient Greece of Croesus, King of Lydia, who inquired of the oracle at Delphi whether he should go to war against the kingdom of Persia. The oracle responded that if he went to war against the Persians, he would destroy a great kingdom. He then attacked the Persians and lost everything, only to realize that the great kingdom to be destroyed was his own.
Socrates realizes that the oracle's statement, "There is no man wiser (than Socrates)" as an amphiboly.
Actually, amphibolies are quite common. Consider the following in a letter of recommendation, "If you can get Sue to work for you, you will be lucky."