Nature is meaningful. However, its meaning is read differently by different kinds of people. A poet's expression of nature is different from the way a scientist interprets it. Both, however, try to see the truth in it. Truth is one and simple, but the paths to it are many and complicated. Each of these paths presents nature's variety.
"If winter comes, can spring be far behind?" asked an English poet. This is true because some temporal events in nature are periodic like the seasons. Time spans like a day, month and year are periodic, too. A week is periodic, but it is not a natural period. It is manmade, so that at an interval of five or six working days we could get a day or two for relaxation and personal work.
Regularity in periods, whether natural or otherwise, sets a pattern and life could be systematised as it would be reasonably deterministic. Events of life are controlled by time and space. However, space is not periodic. Our environment and natural landscapes are not periodic. This irregularity also affects our lives. A person who continues to live at one place does not experience the irregularity of space and hence his life is reasonably predictable. However this kind of life could lack excitement and challenge. On the other hand, the life of a perennial wanderer might be unpredictable and unfulfilling, and perhaps have little impact on society.
Nature being periodic in one aspect and not so in the other is not our doing. Perhaps it is so because otherwise life would have been drab and dull. Natural phenomena are tuned to instill a certain order in life, although at times these appear to occur with some degree of uncertainty. This tends to happen when nature is tampered with unnecessarily.
The situation in matter is somewhat different. A solid matter is largely periodic, so assuming periodicity in the arrangement of atoms in a solid could lead to the understanding of several of its properties quite satisfactorily. This is an example of periodicity in space, which is so useful. The pattern "Again, again, again ... ." is true in matter spatially, but not so in life. In other words, there are no "agains" in life. The following throws some more light on this aspect.
Events in life are not periodic. Childhood, teenage, youth, old age and death – all these occur only once in a normal life. Some times due to illness and accident, some might miss one or two stages. A wise person, according to the Bhagavad Gita, should not worry about these things. Different phases of life are meant for different roles. Just as childhood and teenage years are meant for education, youth is the phase of work.
Periodicity gives rise to regularity; all aspects of life and nature, however, lack this regularity. Through self-control and discipline we can reduce the impact of irregularity and order our lives to some extent. However life no longer follows simple laws. It has become complex because of what we call non-linear responses from the system. It can be chaotic. But once chaos reaches a critical point, the system reorganises itself and order is restored. The Gita says that whenever there is a rise in unrighteousness (chaos) and it reaches a critical value, the system becomes ready for the creation of a supreme process that restores order. But whether this is periodic, we don't know!