Why do I assume that the universe is one and that everything else follows from this assumption?

Thesis: the universe is the only true whole of which everything else is a part.

This is not a necessary conclusion that comes from observation, although observation has not yet been able to credibly contradict such a position. It is rather that my ability to observe as a subject-for-whom-things-matter-because-I-have-to-be-able-to-act-in-the-world, is very limited. Everything I accept and commit to as a belief and which I cannot observe myself to be the case, I need to accept and commit to on trust. There is no other way. Whom and what to trust? Well that is indeed a hard questions to answer and one that will not be answered wholesale. I cannot say: “I shall invest my trust in science” without worrying whether I include bad science under that banner. And how do I distinguish between good science and bad science without investing my trust in those whom I hope know the difference? Even though I am very much part of a community of knowers, if I choose to act on some theory, I shall have to invest my trust somewhere, even if it is my theory. Some parts of that theory will inevitably rest on assumptions I commit to on trust. And so I have to invest my trust in a concept that can be clearly defined but which does not refer to a thing that I can personally encompass fully through observation alone. You might reply to this by saying, “yes, but there are scientists doing that work for you. Surely you can trust them?” My answer is: “sure, but the operative word here is trust. I have to trust something or someone because I must have a concept of my own, however I get it. Without a concept of my own on which to build my thought I cannot ground in reason what I intend to do”. The definition of the universe I use therefore is compatible with scientific thinking and based upon rigorous reasoning, it is this: A universe is a thing conceived like a set that includes everything there is that is capable of affecting everything else.

Elaborated definition: A universe is a system that contains everything that is, everything that can be observed, thought and imagined whether it is or isn’t, in such a way that everything within it can, in principle affect everything else within it.

The universe is the only true whole there is because it may be defined as that in which everything can in principle be affected by everything else. What this means is that if something cannot, even in principle, be affected by something else it cannot belong to the universe and cannot be observed, thought or even imagined by us who are after all part of this universe. The universe is all there is and all there is, is related as one harmoniously working whole. According to this definition, other universes are possible if and only if such universes cannot affect ours in any way, cannot be observed, thought or even imagined. You might at this point laugh and say: “but hey you just talked about other universes!”. I did, but I did not pretend to know whether they exist or what they would be like. I talked about the conditions under which other universes are possible. And it is possible to conceive of other universes only in so far as to establish why they cannot be thought through. As soon as another universe is allowed to penetrate and affect our universe, we can no longer talk of another universe, we can only talk of something within our own universe.

How does this definition of the universe relate to reality? I do not know. Things may well be different but I do not as yet know how to conceive of them differently such that I can still make sensible statements about the world, such that can help me act usefully.

Consequences: Essentially this concept of the universe allows me as a thinking-subject-wanting-to-act-for-the-good to assume that everything can in some intelligible way be related to everything else. That is useful for two reasons. 1. it is useful in that I know that I cannot in principle exclude anything as a possible cause of anything else, i.e. it sets the field of inquiry as wide as it will go, there is no cranny in the universe that I may not explore and 2. it is useful creatively in that it gives me the realization that much is possible.

Another consequence is that this definition of the universe permits Science to explore all the universe for understanding, technology to explore all the universe for use, and art may explore the universe for whatever reason it wants to. Particularly the part about science requires a more in depth argument. Only if we can assume that the universe forms a single whole of working parts can we begin to test its intelligibility.

What happens if I do not assume that the universe is one and intelligible? Nothing much, the universe itself luckily does not pay our philosophizing much heed. It just does what it does whatever silly notions we get into our head. In fact it puts them there! However, in a chaotic universe I may be allowed explanations for events that I do not understand that rely on the notions of the miraculous, the mysterious and on the notions of the unintelligible and inscrutable. Before we knock it, such a position can help. I envy people who, from within the convictions of their religious beliefs can throw up their hands and say: “God behaves in inscrutable ways” and then get on with the bit of life that they think they do understand. However, such an approach does not satisfy me. I would then prefer to say: “I do not understand what is happening here. I hope that one day I will”. From observation and experience I can say that whenever the mysterious or the miraculous is given as a reason, I find it an unsatisfying one. It sets our lack of understanding up as the measure for divine action. Why is what I do understand not divine? What makes incomprehension better than comprehension. Why should divine action not be consistent and perfectly coherent and harmonious? God is surely greater than a secretive manager or CEO who informs their people on a need to know basis. God let’s us admire their creation through understanding. Mind you in architectural design we get this a lot, tutors saying, “well you know, that is just intuitive decision, it cannot be explained, it just is like that”. Nonsense. It can. And it should.

Elaboration: If we were to say that there are many universes then that would require us to either assume that these universes can affect each other, in which case we would need another word for the universe as defined above, which would come down to a trivial semantic tussle. Or we would have to abide by the idea that there are many universes but rest in the confidence that they have no way of interacting with each other so that it becomes impossible to talk about any of them except our own. In that case we are back to where we started.

If we assume that the universe is chaotic in the sense that it is full of incoherent discrepancies and inconsistent moments, not judged from our limited subjective understanding of it, whereby we can attribute those incoherencies and inconsistencies to our limited understanding, but judged objectively, that is relative to the workings exhibited in the parts making up the whole, we would be hard pushed to come to any definition of anything and we would never come to any form of trust regarding our interactions with the world.

So, once we have a single universe of working parts we must assume that the working of those parts is intelligible. Is the condition of a universe being a single whole with working parts whereby every part can in principle work to affect any other part sufficient for us to assume that the universe is also intelligible? The intelligibility of the universe for now assumes more than the definition of the universe given in bold in the first paragraph. If we assume that the universe is intelligible, that is that it can be understood, that it is ‘scrutable’ as David Chalmers put it in his book Constructing the World (2012) we have to assume that the workings of its parts are consistent and stable, that is that some action would have the same response under identical conditions, i.e. that the workings of the universe follow regular patterns that can be described as a calculus or a mechanics, that the whole universe forms a coherent system of consistent workings and that these workings in their coherence are ‘harmonious’ i.e. that each part fits within the whole whatever it does or however it is affected.

To give an example of this last: If my motor breaks down and I remove the crankshaft, this must not have as a consequence that the universe as a whole breaks down. A broken motor does not imply a broken universe. A broken motor may be a lack in harmony of the parts making the motor do what motors should do, but a broken motor is still a working part of the universe that works perfectly as such a working part of the universe. The universe works perfectly whether my motor is broken or not. If this were not so, it would be difficult to imagine how an inconsistent and broken universe could form a single whole of working parts.

Having turned the argument around I now believe we can say that the definition in bold is enough for us to assume that such a universe must also be intelligible in that its workings of parts to make a whole must be consistent and form a coherent whole that works perfectly and is fully harmonious in that sense that everything within it has its place and does what it does. I.e. the universe as a whole and in all its parts is beautiful, if with beauty we refer to whole of working parts that is coherent and consistent with some idea we have of it and that is precisely how I shall use the word beauty. Unpacking the concept of beauty is for a separate chapter.

The opening lines of Spinoza’s Ethics are to me of the same awe-inspiring beauty as the opening lines of genesis. And the fact that I mention them both in the same breath is not for nothing. In Genesis God, pictured as a man capable of walking about in a garden, created the world external to himself as a thing separate to himself. Spinoza performs a Copernican revolution on that image. The universe can only be of one single substance. That substance is God. God is nature.

Challenge: We shall later see how this definition sets up difficulties with the attribution of cause leading to a position whereby it is more sensible to speak of causal competence than of actual cause.

© jacob voorthuis, 2025. Please cite Jacob Voorthuis as the author, The Theoria Project as the title and the page address as the location. This work is licensed under a Creative Commons Attribution 4.0 International License. You are free to: Share — copy and redistribute the material in any medium or format Adapt — remix, transform, and build upon the material for any purpose, even commercially under the following terms: No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made.