To love at all is to be vulnerable. Love anything, and your heart will certainly be wrung and possibly broken. If you want to make sure of keeping it intact, you must give your heart to no one, not even to an animal. Wrap it carefully round with hobbies and little luxuries; avoid all entanglements; lock it up safe in the casket or coffin of your selfishness. But in that casket — safe, dark, motionless, airless — it will change. It will not be broken; it will become unbreakable, impenetrable, irredeemable.
Lewis is referring to what Kierkegaard calls the aesthetic mode of living, which relies on the tactics of rotation and repetition. Rather than living lives of deeper meaning, we cultivate distractions and affairs and pastimes, rotating through them and repeating them to stave off existential emptiness.
I don’t think I’m being dramatic when I say that the West’s response to the crisis of meaning in our lives has been this precise stratagem: “Wrap [our hearts] round with hobbies and little luxuries…” And the web is a catalogue of this exchange. (mills)