So we may feel like we're falling in love in spring or getting depressed in winter, and that's because the biochemistry of the body changes as the Earth transforms itself in these cycles. As the Earth goes around the sun, our bodies change with those cycles. If, as we've suggested, the human body is like a river, constantly in the process of change, then it should come as no surprise that your body is not the same at seven o'clock in the morning as it is at seven in the evening, for example. Scientists call them circadian rhythms, the twenty-four-hour cycle of day and night. These repeating cycles occur in our body/mind as our own biological cycles. It behaves with certain rhythms and cycles of rest and activity. Nature is intelligent. And nature goes to the same place to create a thought, an idea, or a philosophy as it goes to create a liver, heart, or brain, or to create a galaxy, a rain forest, or a tree or a butterfly.

But this outer and inner space is not simply a void, it's the womb of creation, whence everything comes. Science has long been aware of the cyclical character of nature at every level and certainly at the level of human experience. Your appetite is always in the process of change, and so are your cycles of rest and activity, sleep and wakefulness. All of us have surges of energy at certain times and bouts of fatigue at other times. This is true at the quantum level, but it's also something you experience directly through your perceptions. Inside us it is our own inner space, and outside us it is outer space. Ultimately, all of nature comes from this void.