Every word of his novels is gold.
chapter 34 of Milan Kundera's Ignorance
A human lifetime is 80 years long on average. A person imagines and organizes his life with that span in mind. What I have just said everyone knows, but only rarely do we realize that the number of years granted us is not merely a quantitative fact, an external feature (like nose length or eye color), but is part of the very definition of the human. A person who might live, with all his faculties, twice as long, say 160 years, would not belong to our species. Nothing about his life would be like ours—not love, or ambitions, or feelings, or nostalgia; nothing. If after 20 years abroad an émigré were to come back to his native land with another hundred years ahead of his life ahead of him, he would have little sense of a Great Return, for him it would probably be not a return at all, just one of the many byways in the long journey of his life.
For the very notion of homeland, with all its emotional power, is bound up with the relative brevity of our life, which allows us too little time to become attached to some other country, to other countries, to other languages.
Sexual relations can take up the whole of adult life. But if that life were a lot longer, might not staleness stifle the capacity for arousal well before one's physical powers declined? For there is an enormous difference between the first and the tenth, the hundredth, the thousandth, or the ten-thousandth coitus. Where lies the boundary line beyond which repetition becomes stereotyped, if not comical or even possible? And once that boundary is crossed, what would become of the erotic relationship between a man and a woman? Would it vanish? Or, on the contrary, would lovers consider the sexual phase of their lives to the barbaric prehistory of real love? Answering these questions is as easy as imagining the psychology of the inhabitants of an unknown planet.
The notion of love (of great love, of one-and-only love) itself also derives, probably, from the narrow bounds of time we are granted. If that time were boundless, would Josef be so attached to his deceased wife? We who must die so soon, we just don't know.