So with the first post, we asked "What would have to be true of any world that is scientifically observable, regardless of what the specific scientific facts of that world turn out to be?"
We had three answers, and we unpacked each of them. This post is just to sum them up quickly.
X causes Y, and Y is the effect of X. And we saw that if this is true, then X "points to" the production of Y even if Y never in fact occurs. This is also related to the structure of X. The structure is tied to its effect.
Things go from state 1 to state 2. When they were in state 1, they were actually in state 1 and possibly in state 2. So changeable things are a mixture of the actual and the possible. This even applies to things that are physically immobile, because they still have parts that are
Most things in our experience are a mixture of matter and structure. Matter by itself is not an elephant, but the structure of an elephant (the blueprints) without any matter is not an elephant either. It is only the composite of structure plus matter that makes most of these things real. Once again, these things line up with the actual/possible distinction above. Things come into and go out of existence.