Exactly 9 months after being conceived, a man is ushered into the world, a world of consuming uncertainties and unknowns.
Where the only certainty is that life is finite, but as to how and when exactly that is the riddle.
Still, man plods through life making arithmetic calculations and planning, based on dog-eared standards refined through the ages
From the age of reason, that man learns to use Arithmetic to plan and live his life. He plans for the years of elementary, secondary, etc. schooling, the monotonous cadence interspersed briefly with some levity and idleness known as vacations, holidays, etc.
Then he plans for his productive working life, including the idea and feasibility of creating a family of his own. All this, amidst the uncertainty of the length of his life, but guided essentially by the life expectancy table again honed over the ages, taking into account all other elements which may make that life shorter like accidents, sickness, disease, etc.
Past the peak of his mature life, typically human parts start needing attention. Some start becoming bothersome and maybe life-threatening, and thus requiring professional help.
As he approaches closer to his expected life span, tweaked by the many enhancements and modifications that blazing science and technology can offer, his arithmetic calculations take on more certainty, and shorter duration.
In my instance, the most hardy and robust of human organs, the heart has required special and customized attention. It has the close assistance of a pacemaker, or more technically an ICD, implanted cardioverter defibrillator, and for my particular case, a dual-chamber unit, with two leads, one attached to the upper right atrial chamber, and the other to the lower ventricular chamber. Each lead provided with an electrode that will provide the spark when necessary to keep the heart beating normal.
The upper lead will provide the electrical spark that is typically provided naturally by the sinus node in the heart. Absent the spark, the heart may not beat at all and life will be no more.
In my case, my beating heart now uses the pacer for the spark needed 98% of the time, while the lower lead is being used only 6% of time. Per last examination/reading the implanted pacemaker I have still has an expected usefulness of 13 years, taking into account its current usage.
All these details put into context, the more or less exact length of my life. Until and unless a new pacer is installed to replace the depleted one.
This therefore as one can clearly see, puts an arithmetic certainty to the end of one’s life.