First let me acknowledge a job well done. You write well and you've done a good job of capturing these two characters and the conflict between them. There's not much else to say along those lines. You've done what you set out to do.

I'd like to talk about that last sentence. What you set out to do. I think you've set your sights too low. What's missing here is a plot. Lacking that, your characters basically talk to each other about the theme of your story. Themes are the kind of thing that should properly never see the light of day. They work best in the background, providing an invisible force field that organizes the charged particles of your story into a coherent pattern. It is through that pattern that the theme arises.

What might that plot be? Anything is possible. You seem to be leaning in that direction with the rats, but you don't really take it anywhere. A proper plot would provide a framework on which to drape the thematic elements, without calling attention to them. You've already set up a conflict with Ceasar's decision to put the storage yard behind him. Were there to arise a genuine problem requiring direct intervention, rather than just shining a light on a pack of rats, a problem that Ceasar needed to participate in the resolution of, then you would have a situation unfolding for your reader to follow, one that would prompt them to ponder that most essential of thoughts: I wonder what's going to happen next. Right now, there really isn't a next, just two guys talking. You put good words in their mouths and there are valid thoughts behind them, but much of that should be outsourced to your reader, allowing them to come to the conclusions you now feed them. Readers always love it when you leave conclusions unstated, giving them the opportunity to come up with their own interpretations. Such an approach would be especially effective here.