Hamilcar also told Hannibal about elephants and how you must always have plenty of these animals to scare the enemy. He attributed much of his own success to elephants and believed they would have won the First Punic War for him if things hadn't gone slightly haywire; for the war had turned into a naval affair. But even when the fighting was on land, the Romans did not scare nearly so well as expected. The Romans had learned about elephants while fighting Pyrrhus, whose elephants defeated him in 275 B. C., and even before that, in Alexander's time, King Porus had been undone by his own elephants. Thus, if history had taught any one thing up to that time, it was never to use elephants in war.

The Decline and Fall of Practically Everybody (1950) - Part II: Ancient Greeks and Worse - Hannibal