Ancient Rome: bay leaves

She was cooking. "You must not eat a bay leaf," he said.

The Ancient Romans know not to eat bay leaves. Bay leaves were their greatest poison. At least six philosophers died eating bay leaves. "They are not so smart after all," the other Romans said. Doubting philosophy, they decided to trust force instead, and flourished until they were slain.

Caterpillars that hatched from eggs laid on bay leaves were extraordinarily intelligent, with the intelligence of philosophers. Today's Romans are the descendants of those caterpillars.