“It is simply no good trying to keep any thrill: that is the very worst thing you can do. Let the thrill go—let it die away—go on through that period of death into the quieter interest and happiness that follow—and you will find you are living in a world of new thrills all the time. But if you decide to make thrills your regular diet and try to prolong them artificially, they will all get weaker and weaker, and fewer and fewer, and you will be a bored, disillusioned old man for the rest of your life. It is because so few people understand this that you find many middle-aged men and women maundering about their lost youth, at the very age when new horizons ought to be appearing and new doors opening all round them. It is much better fun to learn to swim than to go on endlessly (and hopelessly) trying to get back the feeling you had when you first went paddling as a small boy.”

Book III, Chapter 6, "Christian Marriage"
Mere Christianity (1952)