There are moments, when reading a good book, that certain lines or statements will stand out. Other times, however, entire pages seem to resonate with me in ways that pithy statements never could. In these moments the cadence of an author’s prose and clarity of his logic cause my eyes to glide faster and faster over a page. Pages 218-19 in Suprised by Joy are this way for me.
In his autobiography, Lewis explains that Joy always has an object. Therefore, some things are able to bring more joy than others. The following paragraph is one of my favorites from Lewis’ autobiography.
To cease thinking about or attending to the woman is, so far, to cease loving; to cease thinking about or attending to the dreaded thing is, so far, to cease being afraid. But to attend to your own love or fear is to cease attending to the loved or dreaded object. In other words, the enjoyment and the contemplation of our inner activities are incompatible. You cannot hope and also think about hoping at the same moment; for in hope we look to hope’s object and we interrupt this by (so to speak) turning round to look at the hope itself. Of course, the two activities can and do alternate with great rapidity; but they are distinct and incompatible. This was not merely a logical result of Alexander’s analysis, but could be verified in daily and hourly experience. The surest means of disarming an anger or a lust was to turn your attention from the girl or the insult and start examining the passion itself. The surest way of spoiling a pleasure was to start examining your satisfaction. But if so, it followed that all introspection is in one respect misleading. In introspection we try to look ‘inside ourselves’ and see what is going on. But nearly everything that was going on a moment before is stopped by the very act of our turning to look at it. Unfortunately, this does not mean that introspection finds nothing. On the contrary, it finds precisely what is left behind by the suspension of all our normal activities; and what is left behind is mainly mental images and physical sensations. The great error is to mistake this mere sediment or track or by-product for the activities themselves. That is how men may come to believe that thought is only unspoken words, or the appreciation of poetry only a collection of mental pictures, when these in reality are what the thought or the appreciation, when interrupted, leave behind—like the swell at sea, working after the wind has dropped. Not, of course, that these activities, before we stopped them by introspection, were unconscious. We do not love, fear, or think without knowing it. Instead of the twofold division into Conscious and Unconscious, we need a threefold division: the Unconscious, the Enjoyed, and the Contemplated.
 C.S. Lewis, Surprised by Joy: The Shape of My Early Life, pp. 218-19.