Scientists have identified a number of elemental particles that are not known to be made up of smaller particles. But how do you wrap your head around the idea that something is made of nothing but...itself? Is it absurd, illogical, or just hard to understand?
Now suppose we someday determine that these elemental particles are indeed made of something else. It just pushes the question down a level. The moment we discover the new and smaller substance, we wonder what that is made of, and so on forever, or until...what?
Consider the possible answers.
Maybe everything is made of something else in some sort of infinite series that literally has no start, or it forms a loop of some sort. I can put words to that thought, but does it make sense?
Maybe the elemental particles are indeed made of themselves. But how can a component and the whole be the same? What keeps it all stuck together? It seems irrational.
Maybe there is one undiscovered substance that is the building block of the elemental particles and everything else. This idea has the advantage of simplicity, but it begs the same question: What is that one substance made of?
Or maybe reality is all just one big hologram or illusion that is impossible for the participants to fathom. But who created the hologram? Those guys must be part of a reality that is made of something. The question is inescapable, even if we literally don't exist.
You can even throw God into the mix and it doesn't help because I wonder what he's made of.
There's plenty of scientific evidence that reality is created on the fly by the act of observation, at least in the small world of physics. So perhaps the elemental particles literally did not exist until the first scientists detected them. And so it follows that we can cause the elemental particles to have substructures, or not, by how hard we try to detect that sort of thing. And that process of looking for, and therefore creating, substructures of substructures can be infinite. The problem you might have with this idea is that it implies people are like God, creating reality as we go.
And there's your infinite loop. God is made of people, at least in part, and people are literally creating, through their experiments and observation, the universe. God is creating the universe, while the universe is simultaneously creating God.
Here I remind you not to get your science or religion education from cartoonists. Read the comments to see what parts I got wrong.