Free Will & Possible Worlds

Brigadier Lethbridge-Stewart

Brigadier Lethbridge-Stewart (Photo credit: Wikipedia)

In the Dr. Who story Inferno, the Doctor’s malfunctioning TARDIS console drops him into a parallel universe inhabited by counterparts of the people of his home reality. Ever philosophical, the Doctor responds to his discovery by the following reasoning: “An infinity of universes. Ergo an infinite number of choices. So free will is not an illusion after all. The pattern can be changed.”

While the Doctor does not go into detail regarding his inference, his reasoning seems to be that since the one parallel universe he ended up in is different from his own in many ways (the United Kingdom is a fascist state in that universe and the Brigadier has an eye patch), it follows that at least some of the differences are due to different choices and this entails that free will is real.

While the idea of being able to empirically confirm free will is appealing, the Doctor’s inference is flawed: the existence of an infinity of universes and differences between at least some (two) of these universes does not show that free will is real. This is because the existence of differences between different universes would be consistent with there being no free will.

One possibility is that determinism is true, but different universes are, well, different. That is, each universe is a deterministic universe with no free will, yet they are not all identical. To use an analogy, two planets could be completely deterministic, yet different. As such, the people of Dr. Who’s universe were determined to be the way they are, while the people of the parallel universe were determined to be the way they are.

It could be objected that all universes are at least initially identical and hence any difference between them must be explained by metaphysical free will. However, even if it is granted for the sake of argument that all universes start out identical to each other, it still does not follow that the explanation for differences between them is due to free will.

The rather obvious alternative explanation is that randomness is the key factor—that is, each universe is random rather than deterministic. In this case, universes could differ from each other without there being any free will at all. To us an analogy, the fact that dice rolls differ from each other does not require free will to explain the difference—random chance would suffice. In this case, the people of the Doctor’s universe just turned out as they did because of chance and the same is true of their counterparts—only the dice rolls were a bit different, so their England was fascist and their Brigadier had an eye patch.

Interestingly enough, if the Doctor had ended up in a universe just like his own (which he might—after all, there would be no way to tell the difference), this would not have disproved free will. While it is unlikely that all the choices made in the two universes would be the same, given an infinity of universes it would not be impossible. As such, differences between universes or a lack thereof would prove nothing about free will.

My position, as usual, is that I should believe in free will. If I am right, then it is certainly the right thing to believe. If I am wrong, then I could not have done otherwise or perhaps it was just the result of randomness. Either way, I would have no choice. That, I think, is about all that can be sensibly said about metaphysical free will.


My Amazon Author Page

My Paizo Page

My DriveThru RPG Page

Enhanced by Zemanta
  1. Mike LaBossiere,

    By “metaphysical free will”, do you mean libertarian free will, or otherwise “free will” in some sense that is incompatible with determinism?

  2. Angra Mainyu,

    Like everyone who talks about free will, I have no idea at all what I mean by the phrase. 🙂

  3. Fair enough. 🙂

    I was asking because I didn’t know whether by the “metaphysical” qualifier, you meant to consider only some potential concepts, but leaving aside others, or you were just talking about the usual meaning of the term (whatever that may happen to be).

    So, anyway, if we’re talking about free will in the usual sense of the words (as used colloquially in expressions such as “she did it of her own free will”), then it seems given your analysis to the doctor’s situation that you’re implicitly working under the hypothesis that if determinism is true, we never act of our own free will – your next post about running seems to confirm that.

    If I got that right, I would ask why you think so.

    Personally, I do think we can act of our own free will, but I don’t think determinism would be a problem for free will, though indeterminism might be so (it would depend on the kind of indeterminism). On the other hand, I do not think that my beliefs on the matter are the result of a free choice to believe them, even though my having the beliefs I have is partially caused by previous free choices on my part, like the choice to ponder these matters.

  4. Mike,

    I appreciate your skepticism that multiple worlds can help solve the free will problem. Still, I think it is worth noting that there is at least one recently published paper ( which argues the contrary. On the argument I give, there are reasons to consider many-worlds to comprise the quantum superposition, and free conscious observation an external mechanism that “collapses” the superposition to an observed set of values — such that, in essence, true libertarian free will in a higher reference-frame gives rise to the illusion of causal closure in a physical reference-frame. Just thought I’d draw your attention to it.

  5. Doris Wrench Eisler

    The whole idea that infinite universes implies the realization of all possibilities from our point of view goes right over my head. There always has to be more possibilities than actualities in any one world or universe, therefore, it seems reasonable that infinite universes implies far, far more possibilities than actualities and those typing monkeys will never write Shakespeare, backwards, forwards, in code and every known language – and those unknown for that matter. If universes go in a horizontal line to infinity, the possibilities in them go infinitely in a straight line perpendicular to it. Never the twain shall meet. Unless we factor in unknown, illogical factors. But then, I’m no philosopher. Bear with me.

Leave a Comment

NOTE - You can use these HTML tags and attributes:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>