This question has been bugging me for quite a while now: why should the laws of nature be different for different physical scales, i.e. why should one set of laws apply for very small things (quantum mechanics), and another set for the larger things (classical mechanics, astrophysics, etc.)?
After all, if nature were impartial, there should not be anything special associated with a particular dimensional scale. What is so special about a distance of one micron when compared to one meter? In fact, if all the objects in the universe -- or at least those that we can observe -- increased in size by a factor of ten uniformly, we wouldn't even notice it.
One answer could be that there does exist a uniform natural law, but we are yet to figure it out. If we are able to drill down further, we would find that there is a sort of fractal geometry at work here: each subatomic particle contains a complete, but scaled down, universe within it, with its own galaxies, stars and planets. Brings to mind Blake's immortal words "..To see the world in a grain of sand". BTW, This would require us to handle infinite regression as well, since nothing prevents the subatomic particles of this miniature universe from containing their own miniature universes.
Another answer could be that I am full of shit :-)