I often cite this analogy from Kurzweil’s how to create a mind, I find it useful when we need to travel across levels of abstraction

Let’s think about what it means to be complex. We might ask, is a forest complex? The answer depends on the perspective you choose to take. You could note that there are many thousands of trees in the forest and that each one is different. You could then go on to note that each tree has thousands of branches and that each branch is completely different. Then you could proceed to describe the convoluted vagaries of a single branch. Your conclusion might be that the forest has a complexity beyond our wildest imagination.

How to Create a Mind, by Ray Kurzweil