Many superheroes allow readers to investigate questions of morality, but some introduce deeper philosophical questions. Dr. Manhattan is one of the characters in the classic superhero deconstruction graphic novel Watchmen written by Alan Moore and illustrated by Dave Gibbons. Thanks to the nature of his superpowers, he’s able to see the past and the future much as he sees the present, and because of this, he sees free will as an illusion. This, obviously, makes him an interesting example of philosophical questions of time, causality and freedom raised by his portrayal in the comic.
Dr. Manhattan sees all moments of time simultaneously – more or less. There’s a scene in which the readers are shown his perspective at a certain moment through a series of flashbacks that also tell his backstory. At the same time, he seems to experience himself in the future as well. Admittedly, when it becomes necessary for him not to see what happens later in the plot, a stream of tachyons traveling backwards from something dramatic happening the future obscures his sight of it – which sounds more as if he can see the future, but still exists more in the present, even mentally. As a consequence, he sees everything people do as inevitable – even what he does himself. He also says he’s unable to change what he sees happening in the future. When someone asks him whether that makes him a mere puppet, he replies that “We are all puppets,” and he is “just a puppet who can see the strings.”
This combination of foresight and inevitability raises some odd questions, though. Dr. Manhattan doesn’t always act like he knew everything in advance. He can act as though he’s surprised. If asked about the seeming inconsistency, he’ll explain that he acted the way he did because that was what he was determined to do, and he had no choice about it. Nevertheless, he is sometimes able to predict what other people will do, too, and this holds true despite their protestations.
There seem to be two competing ideas here. On the one hand, if people are told they are going to do something, and they don’t want to do what they are predicted to do, it seems this could lead to them doing otherwise. On the other hand, if, as Dr. Manhattan claims, the universe proceeds along a path strictly determined by the laws of nature and its initial conditions, then shouldn’t it be the case that nobody has any other option about what they will do, and it’s impossible for them to do otherwise? And wouldn’t the same thing follow if someone could see what happens in the future as if it had already happened?
There’s a temptation here to think that “free will” means being able to break free from this causality and contradicts the deterministic picture. This might take the form of thinking that it must be impossible to predict the future like that because free will requires indeterminism that implies the absence of such prediction and determinism. Conversely, if the universe is deterministic, one might think that it’s the idea of free will that must be discarded, and it’s silly to think human choices would be some mysterious exception to this. Both of these options imply that with people not being able to choose otherwise than Dr. Manhattan predicts comes from free will necessarily being something indeterministic and contra-causal, causing things to happen without any prior reason. However, this problem isn’t really about a conflict between free will and causality so much as between causality and prediction.
Causality defines the relationship between events. Everyday perception intuitively sees this relationship as temporal — earlier things causing later things to happen. However, when someone can see the future, there’s a good reason why things in the future should be able to cause things in the present. This happens when Dr. Manhattan predicts what someone else will do; his words in the present are motivated (and thus caused) by what he foresees in the future, the direct result of the event actually happening in the future.
When Dr. Manhattan successfully predicts what someone else will do, the scenario seems consistent. There’s only that nagging feeling that the person should be able to do otherwise in some such situation, something that the comic implies is mere naïveté. If everything and every moment is already fixed, then all events should indeed fit together the way they are shown to do with Dr. Manhattan’s predictions.
Another illustration of what an unchangeable timeline with backwards causation might look like is found in an unrelated comic strip by Alan Moore (from his Maxwell the Magic Cat):
Here, readers can see that even though later moments in time (later panels) affect earlier ones, everything forms a coherent whole. Indeed, the whole series of events is somewhat circular, as if it were giving birth to itself, since the first events are affected by the last ones. This also has the strange consequence that the cat in the later panels gradually becomes a different character than the cat in the earlier panels, even though the conventions of comics imply they are the same character at different moments.
For a similar but less convoluted example from Watchmen, consider this part of a scene between Dr. Manhattan and Laurie Juspeczyk (alias Silk Spectre):
There’s a clear example of causality going backwards here. In the moment shown in panel 3, Laurie ascends the stairs; this causes Dr. Manhattan in panel 1 to predict that she will do so. His prediction causes her to ask what happens if she doesn’t, but his not answering while ascending the stairs in panel 2 causes her to ascend them in 3.
Would it take contra-causal free will to resist this happening? In fact, the answer is no. It wouldn’t even take any kind of choice or agency for this same sort of situation to possibly cause the prediction to be falsified, causing a paradox. All it takes for that is deterministic causation – going backwards.
Consider this version of the events instead. In panel 3, Laurie ascends the stairs. This causes Dr. Manhattan in panel 1 to predict that she will do that. This causes Laurie to resist the idea and, in panel 3, not ascend the stairs.
There’s nothing contradictory about this chain of causation if it’s viewed in the above order. Mere causality should be able to lead to this situation. The contradiction comes when considering the way panel 3 appears in this story; it appears twice, and it has different content each time.
This is a typical paradox of self-reference: when the content of a thing A (in this case a moment in time) is able to affect itself, this may create a contradiction. In the Watchmen example, it’s also essentially the same as the Grandfather Paradox. What happens if someone travels back in time and kills their own grandfather before he has children, since that also implies the time traveller won’t be born and won’t kill him? As far as time travel goes, it’s impossible to say what would really happen insofar as nobody knows of an actually physically possible way to travel in time.
As for questions of freedom and its relationship with determinism and causality, these examples can provide some insights. If Laurie must do what Dr. Manhattan predicts, the problem for her freedom isn’t really that it’s not contra-causal; it’s more that she’s not able to react to what happens around her, such as to resist making the prediction true. It happens naturally enough in the comic, but only because the comic is contrived not to have any contradictions caused by backwards causality.
The aspect of precognition aside, Dr. Manhattan’s lack of freedom really comes from not being able to causally react to information he has when making his choices. If the average person heard Kennedy was going to be assassinated, they could try to do something about it. When Dr. Manhattan sees that it is going to happen, he can’t, because it will happen, and he also sees that he won’t stop it. His actions suggest that maybe it’s not contra-causality or indeterminism that are really needed for free will, but the ability to react to the circumstances that may be perfectly causal. Perhaps the threat to free will isn’t determinism, where only one thing can follow from an earlier state, but fatalism, where only one outcome is possible no matter what happens before it.