I have a pretty good understanding of programming but I don't really see a programming question here, like I said it seems more like a Zen-style definition of the word "into". These ambiguities do bite you in the arse in a specification and that's when you have to nail down what the customer means by "into".
And then there's the definition of a dog? Is it the head, nose, tail?
But after that has been properly defined the programming should be the (often simple) implementation of an algorithm.
What if the forest is not circular and the dog changes direction? In an instant it has moved from 50% through to 90% through. Did it travel faster than light or even instantly?
Much as these musings are interesting I cannot yet see a concrete question about "programming and what is defined and what isn't" and "the terms, declarations and what not".
Rob