This koan takes us directly into a thicket of conceptualization about the nature of Mind -- a thicket where I spend most of my professional life - and shows a path of practice that cuts through it. In traditional Buddhist psychology, there are eight levels of consciousness: the first five correspond to the five senses, the sixth is the level of conceptual thought, the seventh, called Manas, concerns fantasy and imagination, and the eighth, the Alayavijnana, is called the Storehouse consciousness. Why is this monk asking about the sixth level in particular?
Zen is usually presented as a teaching that transcends words and concepts. And here the newborn baby is being offered up as an idealized model of pure unmediated responsiveness -- in the very state the monk aspires to, unburdened by dualistic thinking or conceptual categories of any kind. Some of you may only know Chao Chou (or Joshu) by his famous answer "Mu" when another monk asked him does a dog have the Buddha nature. Here he giving a very different sort of answer to a similarly phrased question about having or not having. With "Mu," Joshu indeed cuts off all conceptual thought. Have or have not vanishes into the Absolute. But here, his answer is a vivid verbal image: "tossing a ball on swift-flowing water." Zen can indeed take us to a place where words lose their relevance, but it also brings us back to the world of free flowing thought and speech. On the one hand, a baby does manifest pure alert responsiveness, uncontaminated by thought -- though infant research now tells us that an infant's world is far more structured by attachment and perceptual discrimination than was once thought. But on the other hand, the baby is buffeted about by its ever shifting moods, by hunger, and the vicissitudes of the responsiveness of its caregivers, unable to soothe or regulate itself very well at all. That's why Aristotle said that nobody in their right mind would ever want to be a child again. Since a child lacks Reason -- and all those conceptual categories we're supposed to be trying to escape - it is at the mercy both of its impulses and of others. So we have to be careful when we start to idealize the baby as embodying some natural, pre-dualistic state. Intellectuals seem very prone to fantasies of sloughing off all their intellectual baggage and returning to some pure, natural or primitive state. Or as somebody once said, Beware of poets who envy panthers! Zen isn't in the business of fulfilling that fantasy.
Chao-Chou's answer expresses the free play and flow of his consciousness. This is what our practice really aspires to. And where we need to practice is to observe what impedes this free flow, - all the ways we try to control the ever shifting free flow of our thoughts and moods. It's as if we all have this little miniature Army Corps of Engineers inside our heads, whose job it is to dam up, or re-direct, or straighten out the stream of consciousness. We need to observe and label all their efforts, all our notions of how we ought to be experiencing our lives moment to moment. We can "answer" this koan by momentarily becoming a baby, but that won't make us act more "naturally" in our daily lives. Only by a practice of labeling our thoughts, over and over and over, watching their flow, seeing them for what they are, and then entering their stream to play and function freely in their midst, only then will we toss the ball back and forth with Chao-Chou.