“If you cross the Halys, you will destroy a great empire.” With this certainty, Croesus, the legendarily wealthy king of Lydia, set out to wage war against Persia in the 6th century BC. He had consulted the priestess of the Oracle of Delphi, the most powerful forecasting institution of the ancient world, and received what appeared to be an unequivocal answer. Croesus crossed the river and did indeed destroy a great empire: his own.

The mistake did not lie with the oracle. Its statement was masterfully ambiguous. The mistake lay with the decision-maker. Croesus, trapped in his desire for confirmation, heard only what he wanted to hear. He reduced a complex, open possibility to a single, linear prediction—one that conveniently suited him.

Thousands of years later, this pattern has not changed. The modern Croesus is the CEO, the minister, or the general. The oracle is the quantitative five-year model. The priestess is the controlling department or the consulting firm. And the question remains the same: “Tell me what the future holds so I can validate my plan.”

When we think about the future, we must let go of our wishful thinking.