Since our life is limited by death, it is also defined by death. Though life and death are opposite, they are closely related to each other, like love and hate. But things are measured not only quantitatively but also qualitatively. Death defines our life in both a quantitative and a qualitative sense. The ancient philosophers argued that the nature, or definition, of a thing is determined by its end.
Death is obviously the termination of life, the quantitative limit.
We experience life. If we focus attention on four words, the daily experience of death might become clearer. These words are, in sets of two, emphasis and ego , and disappointment and death . Marcel challenges this conventional way of thinking by speaking of the ego as a global and indefinable presence. It is an amorphous concept, like that of energy.