Machiavelli said fortune was a flooding river
In chapter twenty-five of The Prince, Niccolò Machiavelli gave one of the most practical pieces of political advice ever written — wrapped in a metaphor about spring floods.
Machiavelli had watched the Medici rise, fall, and rise again. He'd seen Cesare Borgia assemble a state through cunning and watch it dissolve the moment his patron died. He'd seen popes outmaneuver kings. By 1513, writing in enforced retirement on a farm outside Florence, he had a theory.
Fortune, he wrote, is like a river. When it floods, it sweeps away trees, soil, buildings — no one stands against it. But floods happen to those who didn't build embankments during the dry season. The prince who prepares, who builds alliances and fortifications and reserves of goodwill before the crisis, isn't immune to fortune but survives it.
The second claim was harder: fortune favors boldness over caution. A cautious prince waits until the right moment, which never comes quite cleanly enough. A bold prince acts, sometimes incorrectly, but forces events rather than inheriting them.
What makes this unusual for its time is that Machiavelli is not invoking God or destiny. He is saying that roughly half of outcomes are shaped by human preparation and human nerve — and that the excuse of bad luck often obscures a failure to act while the weather was still good.