Life is not easy. Although this seems obvious, what isn't clear is how to deal with this situation. There are so many ways to live our lives and to make them worthwhile and fulfilling, the methods are beyond count. It has been on the human mind since day one (whenever that was), and we're still trying to figure it out. There is one thing we do know: there is no easy answer.
One way to begin sorting things out is to go back to the basics. Something we can all agree upon is that the universe—and everything in it—is in a state of motion. Again, this seems simplistic, but it can lead to some profound realizations. For one thing, there appears to be a sense of order to things; objects do not tend to fly apart for no reason, gravity works in a predictable manner, galaxies are whizzing outward from some center point instead of flying around randomly, and so on. In other words, matter and energy follow strict rules very consistently. Next we can observe that while the rules are stable, all things are in a state of constant change. From moment to moment every object is in some way different, no matter how subtle.
With these observations in mind, it is possible to suggest that one of the fundamental aspects of Nature is that of going. All things change and are in motion. It is, in fact, impossible for any thing not to be so. For thousands of years, humans have tried to explain this phenomena. Of the countless explanations throughout history, they can all be divided into two basic categories: religious and scientific. In the former, the force that drives motion is supernatural, beyond the normal scope of material reality. God(s), spirits, or other intelligent entities are the prime movers, so to speak, manipulating objects from either some cosmic "without" or embedded within objects themselves. In the latter, no supernatural intelligence is necessary for the universe to work as it does. The essential scientific idea is that if it didn't work this way, it would simply have worked another way, and no explanation is needed to explain where the rules "came from." The priority, rather, is to understand what those rules are, especially in such a way as to predict what might happen in the future (e.g. with the understanding of physics, scientists can predict to a precise degree where the Earth has been and where it will be).
Of course, there are ideas that exist on both sides of the religious/scientific divide. However, for our current purposes, we will say, for the moment, that the answer is both ultimately unknowable (or at least unprovable) and unimportant. Whether the rules guiding the universe are intelligent or mechanical in origin, we can agree that they are there.
So, putting aside the question of origin for now, let us continue with the agreement that the universe operates within a set of rules that are based on change and motion. Nature is, in this sense, defined by a constant state of action. We can call the force that underlies this action Universal Will. According to the American Heritage Dictionary, one definition of will is a "desire, purpose, or determination, especially of one in authority." As we've come to understand, this "desire" can be understood, at the most fundamental level, as the drive to go. Although the definition implies an intelligent awareness, as if the universe is somehow "choosing" to behave as it does, this personification is not strictly necessary—it simply helps us to conceptualize the issue. Whether some intelligence is "choosing" it, or it is imbedded in the mechanical operations of Nature, there does exist an irresistible drive that propels all things into motion and change.
Back to Earth
Although we know a lot about the universe (and more all the time), when it comes down to it we live right here on Earth. Life is a whole lot more complicated than "motion and change." This is because all these objects interact with each other, without exception. On the grandest scale, we know from Newton's theory that every thing is in gravitational contact with every other thing, no matter how distant (although the effect weakens over distance). Closer to home, all the interactions that occur between things (air, rocks, water, ducks, tulips, et cetera) inevitably creates interference, cooperation, magnification, alteration, and a multitude of other reactions. The complexity of our ecosystem is mind-bogglingly complex.
So, to help us grasp things, let's take our conceptualization one step further. Although all things in the universe are propelled by the fundamental drive to go, their equality begins to diverge. When we begin to look at individual objects, from the smallest particles to the largest galactic structures, we notice that each type has its own set of features. Of course, we can then look within each large object category (say, "stars") and discover further sub-categories (e.g. red giants, brown dwarfs, neutron stars, black holes, et cetera), each with their own unique set of features. From there, as you have probably guessed, one can observe that every individual item within a category is not exactly like every other. So, as we move from the general to the specific, we notice that categories of objects, and their individual members, all have their own unique ways of going.
Because objects are in a constant state of interaction, part of an object's "way of going" is how it reacts when it comes into contact with other specific objects. So, when an object such as a stream of water comes into contact with the surface of rock, the two interact in a regular, predictable way—for example, the water flows downhill and the rock erodes. In this sense, we can say that when this particular condition occurs, it is the Will of the water to flow downhill and the Will of the rock to slowly erode. The stream and rock are not consciously choosing to behave the way they do, in the sense that they have multiple options and decide to pick one out of a sense of desire. Rather, they are simply obeying their nature. This is the key to understanding the difference between desire and Will.
Much has been written on destiny. For our purposes, destiny shall be defined as the end state of a specific set of actions. Eventually the stream will run out of water and the rock will change its shape. Just as we put aside the issue of religion/science as the source of Will, so will we avoid the question of predetermination. Again, it is impossible to prove if what shall happen in the future is already "written" or if it is a strict matter of chance. Really, this question is simply an extension of the first, since a predetermination would imply some sort of intelligence deciding what the end state shall be, and chance would imply that the universe runs according to mechanical rules.
There is one thing in favor of the chance model—science has yet to find an instance of a physical process (i.e. any observable event) that does not seem to obey fundamental physical rules. True, we find processes that are new to us, and that we don't yet understand. But nothing has been found that contradicts the universe's rule-based system. At the sub-atomic level, it has been well-established that there is a high degree of random activity. On a gigantic scale, astrophysicists are looking to see how galaxies were formed in irregular patterns near the beginning of the universe. All such observations points to the hypothesis that the universe has randomness built into it, and that this randomness is itself one of the fundamental rules for how things work.
Of course, one could argue that this is where a meta-intelligence gets to make little nudges so that things end up where they are supposed to be. Again, this assertion is unprovable either way, and like the first conundrum, is ultimately unimportant. All we need concern ourselves with is that states change Given a certain combination of actions of any object, an end result will occur, granting that there is a degree of randomness (or nudging, if you like) in the universe that prevents any prediction that has 100% accuracy.
To summarize briefly—destiny, for our purposes, is simply defined as the state of an object at some point in the future. We can further assume that this state will be somehow different than it is now. This is the only thing that is 100% inevitable—change will occur.
incomplete...will finish soon...
Who are you? Are you what you do for a living? Are you the sum of your habits, instincts, skills, preferences, and experiences? Are you what you think, believe, feel or behave?