Time Travel Is Sometimes Very Annoying But Not Always

(This article is copied from the Logic of Time Travel blog, here. For some comments, see there.)

See "Time Travel is Always Annoying" by John C. Wright, here.

I will try to summarize:

how can time travel coexist with the appearances both of free will and of cause and effect?;

in Robert Heinlein's "By His Bootstraps," free will is an illusion;

free will seems to exist when you are acting but is seen not to exist when a later you travels to the time of your action;

when you try to change an earlier event, you will find that you have a good reason not to;

this is unsatisfactory because the story stars a robot programmed to think that he has free will although he does not;

each scene makes sense but the whole picture does not;

the character has to be drunk, forgetful, mistaken, ignorant of crucial facts or provided with an artificial reason why he does not want to change the past;

Wilson does not notice that the other guys whom he meets have the same face;

in any such story, the main character makes no decisions and is a passive observer.

I disagree. By "free will," I understand only absence of constraint. "Free will" in this sense is compatible with causal determination of all our decisions and thus of our subsequent actions. Indeed, how else can decisions and actions be explained? Maybe by an uncaused random neuronic interaction, like a cerebral quantum fluctuation? OK. But we do not choose to have one interaction/fluctuation rather than another occur inside our brains. We have no more control over this than we do of any of the external and internal causes that affect our mental processes. So we are "free" only to the extent that we are not constrained. When we make moral or legal judgments about past actions, our own or others', we think of ourselves as agents who could have acted otherwise for a practical reason: we want to influence future actions. On a past occasion, I was tempted, so I "sinned"/offended. On a future occasion, I will again be tempted but this time I will also fear punishment/disapproval so I will be less likely to offend.

A time traveler is just as free or unfree as anyone else. He cannot prevent from occurring an event that does in fact occur but nor can anyone else. Wilson decides to change the course of a remembered conversation by reciting a nursery rhyme but cannot, in the stress of the moment, remember a single nursery rhyme so he instead says something that is appropriate at that stage of the conversation and we can confirm by turning back a few pages that that is precisely what was said at that stage of the conversation.

Wilson I is tired and drunk and thinks that he recognizes Wilson II but cannot place him. Wilson II recognizes Wilsons I and III. None of them recognizes Wilson IV because he is older and bearded  with an air of authority. When he finds that he has good reason not to change past events, then Wilson freely chooses not to change past events.

In Poul Anderson's There Will Be Time, Jack Havig changes not known events but their significance. Thus, the Eyrie recruits Havig and Boris in Jerusalem. When Havig breaks from the Eyrie and organizes against it, he sends Boris to Jerusalem to infiltrate the Eyrie. Havig and his colleagues use their time travel to facilitate the beginnings of a dynamic civilization and to kick-start interstellar travel, not just to manipulate a static society on Earth. Their story moves outward, not just round in its groove.