 Well then, this is nothing but to find the reason and the period for historical changes in the fact joined essentially to human life, that this human life always has an age [a period of time]. Life is time—as Dilthey already made us see and Heidegger repeats to us today; and not imaginary cosmic time because imaginary time is infinite, but limited time, time which grows toward an end, which is the true time, the irreparable time. For this reason man has age. Age is man’s being always in a certain part of his limited time-span—whether it is to be the beginning of his vital life’s time, to be the ascension toward the middle, to be its center, or to be approaching toward its end—or, as one is accustomed to say, whether he is a child, a youth, a mature man, or an old man. (Obras, V: 37)