Destiny? What would a boy know about destiny? If a fish lives its whole life in this river, does he know the river’s destiny? No! Only that it runs on and on out of his control. He may follow where it flows, but he cannot see the end.
Jeong Jeong
Jeong Jeong’s admonishment of Aang is harsh, but on point. Jeong Jeong has the wisdom of a lifetime as a fire bender, and has seen its danger and destruction. In Book 2, Episode 16: The Deserter, Aang learns of this mysterious bender, a former admiral who has left the Fire Nation military. Aang seeks him out and requests to be trained. Jeong Jeong correctly assesses Aang and finds him not unready for training as a firebender. Aang’s trump card, pointing to his destiny as Avatar, only solidifies Jeong Jeong’s assessment. Even granting Aang’s special role and his natural ability to master all of the elements, he knows his path into the future no more than Jeong Jeong does. Aang sees providence in coming across this mysterious firebending deserter, but this is a meaning Aang has assigned, and an assessment that Jeong Jeong doesn’t share.

Jeong Jeong’s river metaphor strikes me as a poignant illustration of the nature of karma*. The concept of karma is often misunderstood. Growing up, I had heard its definition glossed as “what goes around comes around.” If you do good, good will come to you in the future, and if you do wrong, you will pay for it. This is largely correct, but the mechanism of how this happens is what matters. It is not the case that karma is magic that serves as cosmic balancer. There is no being or force watching the world, ready to reward the righteous and punish the wicked. Karma is simply a matter of cause and effect, specifically as it applies to one’s mental states as one takes action in the world. Buddhist traditions have a lot to say about the specific workings of karma, especially as the effects of one’s actions carry over between lives. But you needn’t dive into such esoterica to see karma in action.
When you do something kind, compassionate, loving, or mindful, it changes your mind right then, in that very moment. You become habituated to such action and to the mind states that bring forth such action. Similarly, when you kill, steal, or hurt, you are only reinforcing the greed, hate, and delusion that brought you there. It is you and the mind that you cultivate that will bring you peace and happiness or pain and misery in the future.
Aang sees his destiny as the Avatar. But destiny is an illusion. Like the river, karma is both immediately predictable and ultimately unknowable. We can see the direction the river is flowing, and know that wholesome action will bear good fruit. But the causes and conditions that make up this world are so wide and complex that we do not know what the journey will be like or what the end will bring us. We are swimming in a river of karma. We can cultivate our mind to guide our movement through the river, but we can only know it from the inside.

This confrontation between Aang and Jeong Jeong concludes with the surprise appearance of Avatar Roku, who rebukes Jeong Jeong for questioning the wisdom of the Avatar, the thousand-lifetime elemental master. This only shows what a badass Jeong Jeong really is. After all, he is correct. Aang is too eager in his training, ultimately injuring Katara leaving him fearful of taking up firebending again. The avatar has the wisdom of millenia, the hope of the word on his shoulders, and the confidence of destiny in his favour. But it is Jeong Jeong’s ability to see things as they stand, right in that moment, that proves him right.

* The term ‘kamma’ is used in the Buddhist Pāli texts, but I am using its cognate ‘karma’ here, as it is more recognizable to the general public.