It is easy to see from what we have already said that any collocation of atoms forming a thing could not change its form, unless the barrier inherent or caused by the formation of the present collocation could be removed by some other extraneous instrumental cause. All gross things are formed by the collocation of the five atoms of k@siti, ap, tejas, marut, and vyoman. The difference between one thing and another is simply this, that its collocation of atoms or the arrangement or grouping of atoms is different from that in another. The formation of a collocation has an inherent barrier against any change, which keeps that collocation in a state of equilibrium, and it is easy to see that these barriers exist in infinite directions in which all the other infinite objects of the world exist. From whichever side the barrier is removed, the energy flows in that direction and helps the formation of a corresponding object. Provided the suitable barriers could be removed, anything could be changed into any other thing. And it is believed that the Yogins can acquire the powers by which they can remove any barriers, and thus make anything out of any other thing. But generally in the normal course of events the line of evolution follows "a definite law which cannot be overstepped"
(_pari@namakramaniyama_) or in other words there are some natural barriers which cannot be removed, and thus the evolutionary course has to take a path to the exclusion of those lines where the barriers could not be removed. Thus saffron grows in countries like Kashmere and not in Bengal, this is limitation of countries (_des'apabandha_); certain kinds of paddy grow in the rainy season only, this is limitation of season or time (_kalapabandha_); deer cannot beget men, this is limitation by form (_akarapabandha_); curd can come out of milk, this is the limitation of causes (_nimittapabandha_). The evolutionary course can thus follow only that path which is not barricaded by any of these limitations or natural obstructions [Footnote ref 377].
Change is taking place everywhere, from the smallest and least to the highest. Atoms and reals are continually vibrating and changing places in any and every object. At each moment the whole universe is undergoing change, and the collocation of atoms at any moment is different from what it was at the previous moment. When these changes are perceivable, they are perceived as _dharmapari@nama_ or changes of _dharma_ or quality; but perceived or unperceived the changes are continually going on. This change of appearance may be viewed from another aspect by virtue of which we may call it present or past, and old or new, and these are respectively called the _lak@sa@napari@nama_ and _avasthapari@nama_. At every moment every object of the world is undergoing evolution or change, change as past, present and future, as new, old or unborn. When any change is in a potential state we call it future, when manifested present, when it becomes sub-latent again it is said to be past. Thus it is that the potential, manifest, and sub-latent changes of a thing are called future, present and past [Footnote ref 378].