Enlightening! Thank you for the paper.

Sorry, it was Einstein's theory of special relativity that resolved Hume's insight, not atomic theory. Basically, Hume argued that if you see a ball X hit a ball Y, and subsequently ball Y begins rolling at the same speed of ball X, all one has really experienced is the perception of ball X moving next to ball Y and the subsequent spontaneous acceleration of ball Y. Infinity out of infinity times you may experience the exact same perception whenever ball X bumps into ball Y, but in Hume's time there was no empirical way to prove that the collision of ball X into ball Y caused the effect of the latter's acceleration. With this, you can. I'm afraid I can't answer in any more depth than that, as I myself don't understand the mathematics behind it. Anyone else?