In my schooldays, I read the law of diffusion. It stated that the particles of a solute migrate from the region of higher concentration to the region of lower concentration in a solution. I accepted it as a universal law without ever wondering why it happens so. After many years only, I came to know that it is simply a statistical phenomenon- particles of all the regions tend to randomly migrate in all possible directions, but the particles in the region of lower concentration have to face more resistance from the ones in the region of higher concentration, while the latter face less resistance from the former and hence succeed in migrating from the region of higher concentration to that of lower concentration. This suggests me of a simple principle- that things just happen the way they can, or the way they are allowed to- and the way they happen becomes a law. But as I am not a physicist, I do not know if there could be any truth in it. Here I also want to draw the attention of friends to a related analogy. When matter (and fields) starts its journey in the universe (that is, when they are in the process of forming sub-atomic particles or atoms), there are very less things and they have very limited opportunity to interact, hence physical laws are very strict- there is little chance of variation. After reaching atomic or molecular stages, they get more avenues to interact. This is why, probably, there is a little more liberty in chemistry- one element with different valences and the same elements making different molecules. And when they reach the level of macromolecules or bio-molecules- proteins and nucleic acids, they have much more opportunities to interact, and mutate also, and probably this is why we see so many variations in living beings. I am quite ignorant of physics. I shall be grateful to my learned colleagues if they could guide me whether my intuition- things happen the way they can- may be operating behind other laws of nature, like gravity etc.