"For that matter, there's no reason to believe that the universe itself isn't changing (the scientific word is "dynamic"), to the point where it's never going to be possible to fully understand it because it's different tomorrow from the way it is today."

I ask for enlightenment and I get "Ghost Light." :) Zeno's paradox restated by Marc Platt. If we understand the natural processes by which it changes, then we can achieve a dynamic understanding. If it doesn't change according to natural processes, but changes suddenly and without discernible cause, then we have a clue to the existence of something that is changing it deliberately, possibly to confuse us. But I hope that isn't the case. Either way, the arrow does hit the tortoise eventually, and I'm told there's good eating on one of those.