I have heard some atheists and skeptics about God’s existence claim that the Thomistic doctrine of analogy (i.e., that we can only speak about God by analogy, since we form our concept about God under the influence of empirical impressions of creatures, and so cannot possibly form a univocal concept of God’s essence as such), cannot be right because there is nothing about which we can only speak by analogy. In other words, if we can speak about anything by analogy, then we can speak about that thing univocally as well (followers of Duns Scotus will often press this point). In this post I want to explore a way in which I think the multiverse hypothesis, which is popular among naturalists today, implies that there are some things, after all, about which we can speak, write and think, only by way of analogy, or at least by way of analogy alone.
There are a few different definitions of the multiverse hypothesis, but I will here take the multiverse hypothesis to be the thesis that there is an ensemble of universes, including our own, all of which have their own entirely separate spaces and times. On this hypothesis other space-times exist, but, it turns out, their spaces and times are incommensurable with our own. Everything may seem fine so far, but an interesting thing happens when we reflect more deeply on this (hypothetical) situation. It turns out that, in a rather straightforward way, the space and time of any alternative universe isn’t really what we refer to as space, or what we refer to as time. It makes no sense to ask ‘how far away’ an object in the space of another universe is, or ‘how long ago’ an event in another universe was, precisely because those universes do not share our time, or our space. It makes no sense to ask how old another universe is compared to ours, or how large another universe is compared to ours, for they cannot stand in such relations to each other. Those comparisons break down at this level because they become semantically vacuous. Such relations simply do not obtain between different universes.
This makes clear that our time is what we refer to when we talk about time, and our space is what we refer to when we talk about space. We are, when conceiving of other universes, taking our concepts of time and space and saying of a reality actually incommensurable with our own that it is ‘like this.’ That, however, is just to say that we are using our concepts of space and time analogously, and this is precisely the way in which the Thomist thinks we can, and must, speak about God. These other universes do not literally or univocally have any space, or any time, where these words are understood in their literal senses. You can satisfy this for yourself by thinking through some obvious considerations; for instance, consider that anything extended in time is, by logical necessity, earlier, later, or simultaneous with all other events in time. In the case of another universe this is not so, for anything extended in the ‘time’ of another universe is not earlier, later, or simultaneous with all other events in time. The same can be said of space, since any two (non-identical, non-overlapping) things extended in space are, necessarily, some distance apart from each other, but objects extended in different spaces are no distance apart from each other. The only way to make sense of talk of spaces and times incommensurable with our own is by analogy; we can speak about other space-times only by adopting a propositional attitude according to which we recognize our statements to be predicated by way of analogy. Our terms are inherited from the world with which we are familiar, and we are using them to speak about realities which we otherwise (than by analogy) cannot speak or think about at all. Nevertheless, the multiverse hypothesis can be both coherent and even true.
If I am right, then what this shows is that analogous predication is coherent and legitimate after all, at least if the multiverse hypothesis is a coherent hypothesis (it may not be, of course, but at least the naturalist/skeptic who takes it to be a coherent hypothesis will not be able to turn around and say that the Thomistic doctrine of analogy must be wrong because there isn’t anything about which we can speak only by analogy). Perhaps the naturalist will recoil at this point and argue that even if different universes have incommensurable times and spaces, that doesn’t mean that there is no way to predicate anything univocally about these different universes. For instance, perhaps two universes can stand in some real relation (for instance of similarity) to one another, or perhaps we can say that both exist in exactly the same sense of ‘exist.’ In response, I want to say that I am doubtful that any two universes can stand in any real relation to each other at all (I think this is ultimately a linguistic confusion), and even if many different universes could be said to exist in a univocal sense, their spaces and times considered as such could only be described and conceived of by analogy with our own. Perhaps it is not inappropriate to point out, as well, that existence is not a first-order predicate anyway (a point with which the naturalist will almost certainly agree), so that the fact that it can be applied apparently univocally shouldn’t worry us precisely because it isn’t a property. As such, it contributes absolutely nothing to the idea of the thing in question, and the doctrine of analogy maintains that it is our idea of the thing which can be formed exclusively by analogy.
Another objection may be that space and time are complex ideas which are conceptually formed by putting together combinations of simpler ideas, each of which can, as it turns out, be used univocally as applied to our universe and to others. For instance, somebody could suggest that time is nothing other than the direction of increasing entropy, and that ‘entropy,’ ‘direction’ and ‘increasing’ are concepts which can be applied univocally across different universes. I think that this is wrong for a few reasons. First, ‘direction’ doesn’t seem to be univocally applied across different space-times (maybe it is, but it isn’t clear to me that it is). Second, I see no reason to think that time is defined by the direction in which entropy increases. In fact, the only reason we think of entropy increasing over time is because as time passes we observe an increase in entropy, but had it been the other way around we would have defined time as the direction in which entropy decreases, and, indeed, there are presumably some (at least possible) universes in the multiverse in which, as time goes on, entropy does decrease – and if this is even possible, given the multiverse hypothesis, then time cannot mean merely the direction in which entropy increases. If time simply meant the direction in which entropy increases then a universe in which entropy decreases over time would be physically impossible, but that, as far as I know, is not the case (perhaps someone could raise a quibble here about the second law of thermodynamics, but that is articulated precisely with the presumption that it is about our universe). Moreover, if one simply defines time as the direction in which entropy increases then I think it follows trivially that in no universe is it physically possible for entropy to decrease over time, but there is no good reason at all to accept this definition of time, and there are some very deep philosophical reasons for rejecting such a definition. In any case I think our concept of time is more primitive and basic than our concept of entropy; we discovered that entropy increases as time passes, but we did not and could not have discovered the reverse.
In conclusion then, it seems to me that the naturalist faces a dialectical dilemma here. Either analogous predication is coherent and legitimate, in which case we can countenance both the doctrine of analogy and the multiverse hypothesis, or else it isn’t, in which case we cannot. If the naturalist wants to appeal to the multiverse hypothesis, even as a merely coherent hypothesis (for instance, as a possible explanation of the appearance of fine-tuning), then they will have to concede to the Thomist that we can, in principle, speak about God by analogy alone (not to be confused with the concession that we can only speak about God by analogy).
 See: Thomas Williams, “John Duns Scotus,” in The Stanford Encyclopedia of Philosophy (Summer 2015 Edition), Edited by Edward N. Zalta, http://plato.stanford.edu/entries/duns-scotus/#NatThe
 For more on this topic please visit: http://www.reasonablefaith.org/questions-on-the-arrow-of-time