Divination was used for thousands of years in ancient Mesopotamia to guide military and political decisions. The decisive factor here was not the oracle, but its interpretation. This also applies today: The events of 2017 cannot be predicted by astrologers, but they can determine their Interpretation of Dreams Ibn Sireen (تفسير الاحلام ابن سيرين).
“Predictions are difficult, especially when they concern the future.” This extraordinarily lucid phrase is attributed to Mark Twain, Winston Churchill, Karl Valentin, and Niels Bohr. All of them probably said that sentence, just at different times. Be that as it may if the explanation of what has been is as difficult as the determination of what is yet to come.
Oracles are not self-explanatory
That was already the case with the ancient Greeks. The famous Oracle of Delphi: There sat a priestess over a crevice from which fumes rose, clouding the spirit of the lady. In plain English, she was stoned all the time and was constantly mumbling weird stuff, which was then interpreted by Oracle experts.
In ancient Rome, the state-employed augur read the will of the gods from the flight and screeching of birds and other animals, or from their bones and entrails of lamb, pig, chicken, and fish. It probably depended on what the fortune-teller in question liked to eat.
The decisive factor here is that oracles are not self-explanatory. You have to be able to interpret. Before his campaign against the Persians, the Lydian king Croesus consulted the oracle of Delphi and received the answer: “If you cross the Halys, you will destroy a great empire.” His oracle specialists were probably not among the smartest. The result of the campaign was the destruction of his own empire.
In the interpretation there is only a yes or no
But there are also success stories. Long before the ancient Greeks and Romans and Lydians, Sumerians, Assyrians, and Babylonians had specialized in taking advice from animal entrails. The ancient orientalist Stefan Maul has examined their art of divination and found out.
“An important decision in the military and politics, including personnel decisions in the ancient Orient, are not made without carrying out an evaluation by means of such a visceral examination.”
The result; the peoples of ancient Mesopotamia were extremely successful politically, economically, and militarily for thousands of years. The trick here is that the interpretation of the oracle is not particularly complicated because there are only two possibilities.