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In my last post, I pointed out that the movie Tenet argues that we lack free will and explained why that is likely correct. The realization of this fact has pushed some to conclude that nothing they do matters, and thus that they should do nothing at all. “If my fate is sealed, then I might as well do nothing. What’s the point?” But this fundamentally misunderstands the above fatalist conclusion—and brings us to Tenet’s second philosophical message.
At the end of the film, when Neil heads back into the final fight scene, knowing he is about to be killed, the Protagonist once again asks: "But can we change things? If we do it differently?” Neil answers with a smile: "What's happened, happened. Which is an expression of faith in the mechanics of the world, not an excuse to do nothing."
And he’s right. Fatalism does not entail that your actions don’t matter—that, regardless of what you do, the same thing will happen. To see why, consider the failed “backtracking counterfactual” solution to the freedom foreknowledge problem.
The freedom foreknowledge problem suggests the fact that God knew yesterday what you would do tomorrow entails that you cannot act freely. If God knew yesterday that you were going to do X tomorrow, since God can't be wrong, you could do nothing else but X tomorrow. And if you can't do otherwise, you can't act freely.
In response to this problem, some observe that, despite all this, the following counterfactual is true: “If I don’t do X tomorrow, God wouldn't have believed yesterday that I would.” If I don't do what I will do, God's beliefs would have been different than they were. And this seems right; that counterfactual is true. God’s past belief was caused by my future action, not the other way around—so if I were to act differently, God would have believed something different.
Now, how this argument fails is as a solution to the freedom for knowledge problem. The fact that “if I were to act differently, God would have believed differently” doesn't entail that I could act differently. My future action is still inevitable and thus not free, despite the fact that God's past belief would have been different were I to do something else.
Indeed, God's past knowledge entails that my future action already exists; it's already on the timeline. It's a fact. And in order for me to freely do X, my action of doing X and my action of not doing X have to be equally possible. If my action of doing X is already a fact, clearly, that is not the case. If God already knew I would do X, I can do nothing else.
But what this argument does reveal is that our actions are not without consequence; things wouldn’t be the same regardless of how we act. Even if my future actions are fated, and thus I can’t do any other actions but those that I will do, it’s still true that if I were to act differently, things would be different—in many cases, grandiosely so—and so it very much matters what I do.
Think of it this way: On a certain limited interpretation of fatalism, it doesn't matter what you do. Suppose the prophecy that Oedipus will kill his father means that no matter how he or his parents respond to this prophecy, it will come true. If they throw him in a ditch, he will grow up and meet his father at random and kill him. If they raise him, he will kill him because he grows to hate him. There are multiple paths Oedipus could take, but they all end in the same place: Oedipus killing his father. If that’s what we mean when we say some event is fated—yeah, it doesn’t matter what you do.
But that’s not what the fatalism we have been discussing entails. On the view we have been discussing, there is only one possible future, and thus only one possible way to get to any fated event. If one event were different, an entirely different future could emerge. Of course, it won’t—only what is fated will occur. But that doesn’t mean that whatever action you are about to take doesn’t matter—that if it didn’t occur, everything would just be the same. The decision you are about to make may not be a free decision, but it could also be the causal factor that determines the future—it could be the cause of what has been fated to happen since the beginning of time.
Indeed, this is what Neil realizes at the end of the film; his decision to go back into the fray (and die!) is necessary for them to have won the day and saved the world. As the Protagonist puts it at the end of the film, as he ponders his inevitable future as the one who will form the Tenet organization that pioneers the time-reversal technology that sets the stage for the film and makes the success of their mission possible: "We're the people saving the world from what might have been... The world will never know what could've happened...”
Indeed! And we will never know what the future might have been. But that doesn’t mean that the future that will occur would still occur regardless of what actions we take. Our actions matter. And so fatalism is, indeed, an expression of the “mechanics of the world, not an excuse to do nothing."
To say the least, a movie that can embody, and even communicate, such a deep philosophical lesson is a masterpiece indeed. Christopher Nolan has done it again!
Copyright 2020, David Kyle Johnson
