7 Days of Nothing, #5

Today I thought about how to define things as being inside other things. Is it when something is fully contained by the container? When no part of the object extends beyond the container’s volume?
I feel like this is a good start, so let’s test it: I put a pencil in a short glass. Is it in the glass? I think so, but it isn’t fully contained. I put a slice of cheese on a plate. Is it in the plate or on it? It is contained by the volume of the plate, but “on” is more natural than “in”. Consider a cat sitting in a box. The cat is not fully contained by the box, yet we say “in”. How low can the edges of the box (or conversely, the height of the cat) go before the cat is “on” the box? And this isn’t even including weird containers like foil or the sky. Let’s look at those. At what point does a plane in the sky transition to being in the general air and not in the sky? If I set a sandwich on a piece of foil and start to wrap it, there’s a point at which it’s no longer on the foil, but in it. Where’s that point? I don’t know. Maybe you have a better answer. Anyway, I hope this was at least mildly interesting.