A person who thinks all the time has nothing to think about except thoughts. So he loses touch with Reality, and lives in a world of illusion.
Alan WattsYou will begin to realize that if you contemplate long enough on the leaf of the flower, that it involves the whole universe.
Alan WattsIt seems to be the special peculiarity of human beings that they reflect: they think about thinking and know that they know. This, like other feedback systems, may lead to vicious circles and confusions if improperly managed, but self-awareness makes human experience resonant. It imparts that simultaneous "echo" to all that we think and feel as the box of a violin reverberates with the sound of the strings. It gives depth and volume to what would otherwise be shallow and flat.
Alan WattsTo go out of your mind once a day is tremendously important, because by going out of your mind you come to your senses. And if you stay in your mind all of the time, you are over rational, in other words you are like a very rigid bridge which because it has no give; no craziness in it, is going to be blown down by the first hurricane.
Alan Watts