the multiverse is a plausible position to accept and to demonstrate that, even within the scientific community, there is no single viewpoint on just what a multiverse may look like.5 Megill gives five reasons for the acceptance of the plausibility of the multiverse: (1) that his premise that a multiverse is possible is so weak that it is plausible, (2) that it has not been conclusively shown that a multiverse does not exist, leaving it epistemically possible that there is one, (3) that it is entailed by several current theories in physics, (4) given that it is entailed by current theories in physics it cannot be denied by some of the most likely opponents, and (5) that denial of the multiverse theory would strengthen the theist’s position by leaving God’s creative act as the only possible explanation for the fine-tuning, thus making such a denial imprudent for the atheist (Megill, 2011, p. 131).
While the structure and overall argument forwarded by Megill differs, both in its motivation and in the kind of multiverse that it proposes, from the argument presented by Donald Turner (Turner, 2004) the two appear to share some common ground. Much like Megill, Turner argues for a multiverse6 that is composed only of universes7 with a “preponderance of good over evil” (Turner, 2004, p. 158). So, while Turner acknowledges the possibility of a multiverse containing every logically possible universe, he argues that if his account is to stand up to the problem of evil, then the threshold below which God chooses not to create any universes is the balance between good and evil. That is to say, on Turner’s account, no individual universe will contain more evil than good, and thus no universe in the multiverse will be on-balance bad.
A further alternative viewpoint on the multiverse is presented by Hud Hudson who suggests, rather than the series of spatiotemporally isolated universes that are typically proposed in multiverse theories, what he calls a hyperspace (Hudson, 2005). Hudson’s hyperspace is essentially an additional dimension to the three dimensions of time-space that we are accustomed to. Hudson describes his hypothesis of a plenitudinous hyperspace by saying that “spacetime is a connected manifold with more than three spatial dimensions, yet the manifold can be partitioned into subregions which vary independently with respect to their cosmic conditions” (Hudson, 2005, p. 40). So while the language used to describe Hudson’s hyperspace varies from the language of other multiverse theories, the product still seems to be quite similar: a series of universes, or regions, that exhaust a wide variety of cosmic conditions. In discussing his hyperspace model in relation to the fine-tuning argument, Hudson says the following:
[G]iven the fine-tuning, the hypothesis of a plenitudinous hyperspace should of itself lead us to very high expectations that the cosmic conditions will be life-permitting. Why? Presumably because, on the assumption of a sufficiently rich plenitude, there will be enough distinct regions in which the physical parameters differ independently to render it unsurprising that at least some of them fall in the life-permitting range. (Hudson, 2005, pp. 41–42)
So while this is a specific discussion of hyperspace that is preferential to a three-dimensional conception of time-space in relation to the fine-tuning argument, it does a good job in illustrating the composition of Hudson’s account. The two prime elements that differentiate Hudson’s account from others seem to be that, first, Hudson’s account speaks of different regions being found in different dimensions of space-time rather than merely different universes being found in different spatial or temporal locations that other multiverse accounts appeal to.8 In having a series of different universes existing at different space or time locations there does not appear to be any need to invoke an extra dimension of space-time to accommodate for the existence of other universes, but this is not the case for the hyperspace account. And secondly, while many other multiverse accounts often maintain that different universes within the multiverse are spatiotemporally isolated from one another, it is not the case that the same isolation is necessary or present between regions in Hudson’s account, in that it seems to leave open the possibility of accessing one dimension from another dimension or of accessing one region from another region. Of course, the practical implications of crossing such dimensional or regional lines is an entirely different discussion but, that aside, there does not seem to be anything inherent in the hyperspace account that precludes such a traversal.
Coming from different motivations, Klaas Kraay proposes a unique multiverse account that he sees as a response to the “best possible worlds” objection to theism (Kraay, 2010). Kraay argues that the best possible world need not be equated to a single universe and that the best possible world can actually be a set (possibly an extremely large or infinite set) of universes. Given the nature of God, an unsurpassably good being, He would create all of the universes that are worth creating (Kraay, 2010, p. 360). That is to say; given some vague threshold of goodness that determines whether a particular universe is worthy or unworthy of God’s creation and sustenance, for any universe above that threshold, God would create and sustain it. The total collection of all of these universes that are worthy of creation and sustenance would then collectively comprise our world. A world which contains a number of worthy, spatiotemporally disconnected universes. Kraay calls this the “Theistic Multiverse” (TM), and in TM, “God creates and sustains all and only those universes which are worth creating” (Kraay, 2010, p. 363). Because of the nature of God and the structure of this world, Kraay concludes that if one accepts various principles that he has put forth9 “are plausible, and if TM is logically possible, the theist must maintain that the actual world is TM, and that it is the unique best of all divinely actualisable worlds” (Kraay, 2010, pp. 364–65). So on this account, Kraay argues not only that a multiverse is a logically possible world but that the theist ought to accept that it is the actual world, and subsequently that it is the only possible world, simultaneously rendering it the best possible world.
The final account to be discussed in this section is one that I am currently developing and it hinges on the nature of the relationship between God and free will. If it is plausible that free will is the greatest possible good,10 and God is all-loving and perfectly good,11 then it seems that God would be required to maximize the amount of free will in the universe.12 Since free will is not something that can be measured qualitatively, since my free will cannot be better than your free will, it must be measured quantitatively. That is to say, for God to maximize the amount of free will in the universe, He must quantitatively maximize the number of instances that free agents exercise their free will. Imagine that each free choice made by each individual in our universe counts as one unit of good. So, my choosing to have granola for breakfast is one unit of good, my choosing to put strawberry yogurt on that granola is a unit of good, my choosing to eat my granola and yogurt from a particular bowl is a unit of good.13 Similarly, I could have chosen to have oatmeal for breakfast, I could have chosen to put brown sugar on my oatmeal, and I could have chosen to eat it straight from the pot in which I made it. Supposing that these two different breakfast scenarios are mutually exclusive and the only options available, I could have only actualized three of six decisions, and thus only garnered three units of good while leaving three units of good untouched. In order to create a maximally good universe, however, God must have it so that no units of good are left untouched. For this to happen, another universe in which I decide to eat brown sugar oatmeal out of a pot for breakfast must be actualized somewhere. For this particular example, the existence of these two universes would exhaust the number of free choices available, thus maximizing the number of units of good that are enjoyed between the two, which creates a maximally good multiverse.
Of course, the example just presented is exceptionally simplistic and limited in scope, but is introduced merely to illustrate how this multiverse model works at its most basic level. We could imagine a similar situation in which eating Froot Loops, eating a bagel, and not eating breakfast at all are all available free choices and that for each one of these options there is an actual universe where it is actualized. Similarly, this process would be carried out for each free choice made throughout the lifetime of each individual agent, and so too would each possible collective conjunction of free choices between other free agents. This would result in an enormously large number of distinct universes that ultimately exhaust every possible free choice and combination of free choices, leading to a multiverse that
