Here I'm going to attempt to answer the first mover argument. The first mover concept is argued as follows:
“Oh, so the universe just created itself? That’s your answer? Everything just came from nothing? You atheists are the ones who believe in magic.”
The exact same argument in the other direction, used to rebut this, would sound something like “a magical sentient being which poofed itself into existence is no more rational of an answer.”
I’m not insulting the intelligence of religious people, or atheists, (for all I know there could theoretically be a personal god, and there could just as easily be none, I don't claim to know for sure). In this piece, I’m going to attempt to stamp out this ever present “what created reality vs what created god” debate.
The problem with either argument is that it fallaciously assumes the premise that existence is limited to a linear timeline of constant cause & effect relationships between infinitely divisible, separate events. In other words, you’re incorrectly assuming that at one point there was no existence, and then after that, (due to some cause), existence began, therefore during the time of nonexistence, something must have caused the effect that is existence beginning. To simplify matters; if god exists, then said god would fall within that umbrella of “existence”. The fact is, for existence to happen, it must have “always been”, because time is empirically not the only dimension of existence. Dimensions exist that are not time, such as length, width, and height, (including all of physicality as we know it). For those physical dimensions to exist, they cannot possibly be inseparably bound to the time dimension, because if they were, nothing physical could ever begin to exist, as a linear timeline of cause & effect relationships involving nonexistence of objects followed by existence of objects, would require something to come from nothing; for existence to be an effect of a causal nonexistence, which is clearly impossible. You cannot derive one from zero no matter how hard you try. Just as a god of infinite power logically could not create a rock too heavy for himself to lift, a god would still be bound to the unbreakable laws of logic, one of which being that no quantity of anything - other than zero - can be derived only from zero. In other words, something cannot come from nothing, and a god could not possibly change that. No matter how powerful, a god could not make zero plus zero equal one, which applies as much to itself as to physicality. Existence cannot be the effect of a cause within a realm of nonexistence, because in a realm of nonexistence, nothing (including any such cause, or any god) exists. Nonexistence therefore cannot be considered any sort of “starting point” for our universe, it’s simply the inconsequential plane of reality in which no dimensions are applied. Nonexistence has no place in the dimensional plane which involves physicality and time, the one we knowingly live in. There could never have been nonexistence in our linear timeline; existence always was.
For dimensions such as length, width, and height to exist, therefore, they must exist independently of the time dimension, thus outside any spectrum of cause & effect.
All dimensions of physicality must exist independently of time, in an eternity. What we would find ourselves experiencing if we suddenly phased out of the dimension of time while physically staying put, is everything that can ever happen, happening all at once, forever. In the eternal plane of existence, as everything which can ever happen is simultaneously happening, there is no such thing as a cause & effect relationship because eternity is, by definition, outside of time, while cause & effect is the inherently linear concept of X being followed by Y as a result of X. Eternally, all of existence is one single event, which can happen in no “order” because an “order” requires a linear timeline which, as shown above, physical existence cannot be inseparably bound to. Eternally, therefore, there is no such thing as a cause & effect relationship, thus all manifestations of dimensions other than time - all forms of matter and all empty spaces - are not effects of a cause, they “always were”, without a beginning or an end. Multi-dimensional existence (such as all 3D objects), to occur in a linear timeline (like us), must also exist in a timeless frame, because the dimensions of length, width, and height, which comprise physicality as we know it, have to exist not only in congruence with, but also independently of, the time dimension, otherwise they couldn't have started existing. In other words, everything that exists in time also exists outside of time. In a linear timeline, anything that can happen, with enough time, will eventually happen. All of existence in a timeless frame - all of physicality - is one simultaneous occurrence which was bound to happen, because it can happen, you could say it has “all the time in the world to happen” because time is not a factor outside of its own limited dimensional territory, the dimensional planes in which time is overlapping with other dimensions; such as the one we know we live in. The 4 dimensional plane we live in (length + width + height + time) cannot be the only dimensional plane, for anything to exist, for the reasons stated above. Physicality cannot begin with the absence of physicality. There has to be a plane of existence in which everything ever to happen is happening simultaneously, and infinitely in both directions - "past and future" - due to the absence of the time dimension, for us to experience this plane of existence in which anything is happening in sequence. In other words, for the physical world to be possible, it must be separable from time.
Forgive my unavoidable redundancy here; every dimension must be alienable from the others. Every possible manifestation of existence within the frameworks of length, width, or height, or any combination between them such as length + width + height (the one we can readily comprehend), exists in harmony with every other possible combination of dimensional layers, such as combinations both including and not including the time dimension. All dimensional planes that do not include the time dimension, comprise our eternal reality. All manifestations of physical dimensions must be separable from time, existent in an eternal reality, to be possible. The manifestations of eternal reality - everything that ever exists - can still be experienced in a linear plane, because the other dimensions do also overlap with time, just not exclusively. Because the dimensions of physicality cannot exclusively exist in an overlap with time, they cannot be bound to a linear construct of cause & effect. So we do not need to try to assign a cause to the effect of existence, the existence of our physical universe is not an effect of a cause.
I prefer to keep it as simple as possible. Proving that God cannot possibly exist is easy enough but when they counter with some variant of "well then where DID the universe come from?" I just honestly answer, "I don't know." Christians preach that humility and honesty are virtues so they should, on some level, be able to respect such an answer. We can develop theories by referring to various bits of evidence that we find but we can never know such a thing for certain. Personally, I don't even care because the answer has no pratical bearing on me or anyone else whatsoever.