Life survives because the entity is capable of rejuvenation. Much of what happens in the processes of rejuvenation is involuntary. These processes include sleep (where cells rejuvenate), breathing (through which oxygen runs through the veins with the help of blood cells to transfer energy), and food (which supplies yet another form of energy to keep the cells going). The processes are many and an understanding of human anatomy is necessary to appreciate the fundamental role rejuvenation has in keeping a live body alive. Add to it the power of the mind and one would understand the role of intelligence in directing the body. Spirituality is an essential component though regrettably not often factored into the thinking process on rejuvenation.
As just elaborated, rejuvenation processes lay the foundations of life. Since the essential elements of such rejuvenation are involuntary the physical body keeps operating.
There is another component of rejuvenation which requires conscious thought. For want of a better...