This process (reputedly developed by Aristotle) is called deductive reasoning ("top-down" logic). From a general rule (major premise) there then follows the narrow range of specifics under consideration (minor premise); and finally the conclusion is drawn. This contrasts with inductive reasoning whereby the conclusion is reached by extrapolating from specific cases to a general rule. It is commonly accepted that deductive reasoning is more trustworthy than inductive leaps. Nonetheless sound reasoning naturally depends upon the validity of the premises (major or minor) which is where the personal skill of analysis and argument (in the rhetorical sense) becomes evident. I judge it mandatory to avoid purely florid thought by preserving a clinical scrutiny.
The past is mildly entertaining. The future is unimaginable. The present is the only legitimate absorption, unfettered by disturbing recollections, loss of youth, dwindling friendships, false ambitions, worrisome possibilities or unreality. The provocation of the present is far more temperate and authentic, a workable and manageable consideration. By definition the focus upon the present eliminates two potentially disfiguring polarities (the past and the future). If one inclines to view this disparity as escapist for example, it requires only an admission that we are but the current history of all that has transpired in our experience. It is absurd to imagine we are a product of anything but our past (apart from limited and obvious genetic inheritance).
What, you might ask, is the point of this navel gazing? It enables ones to rise above the irreversible past and to avoid the incalculable future. The object is entirely utilitarian. And like so many other instances, simple is good. It is also a useful reminder that no amount of brooding will further the improvement of life, either for oneself or others. The only practical evolution lies in current behaviour, a vernacular which significantly remains static unless motivated by action. All the philosophical projection in the world will do nothing to change it until there is performance, a result which is pointedly predicted by intent. Until there is an appetite for staging there is no achievement. It also means that the paralysis of debate is relinquished. In its plainest terms the gusto for life reduces to what is here and now, not what was or what might have been or will be. For me it is a liberating consolation to my personal inadequacies. The posture further legitimizes a laissez-faire attitude and strengthens a disregard of pointless anxiety.