Pain makes a more definitive appearance during a flashback where Orochimaru recalls Itachi joining the Akatsuki.
Before Nagato ever declares “Pain is what allows the world to grow,” the series establishes a universe drenched in loss. Naruto’s childhood loneliness, Sasuke’s clan massacre, Kakashi’s grief over Obito and Rin, and Gaara’s loveless upbringing all serve as early sketches of suffering. Yet in these early arcs (Land of Waves, Chunin Exam, Sasuke Retrieval), pain is largely individual—a tragic origin story to overcome. It is not yet a philosophy. When Naruto defeats Gaara by sharing his own loneliness, the message is clear: empathy can break the cycle. Pain, at this stage, is a wound that bonds people.