Sleeping has always fascinated me. We do it for almost a third of our lives and we associate so much ritual with it. It strikes me as curious that we purposely stretch out on a carefully made bed for seven or eight hours when we could be accomplishing great things. Why do we do it?

In Greek mythology, Sleep was considered the younger sister of Death, and for some time scientists and doctors thought sleep was a lesser form of death. Textbooks contained diagrams showing a progression from wakefulness to sedation to sleep to anesthesia to coma to death.A visit to Plimouth Plantation reveals that Pilgrim homes did not leave very much room for sleeping. Their beds were short by our standards and people in those days apparently slept sitting up. In the 19th century, four poster beds had curtains that dropped to keep out dangerous vapors.

Sleeping rituals have varied enormously over the years, but most of us are convinced that sleep itself is important for us. Shakespeare called sleep "Chief nourisher in life's feast," and he also spoke of "Sleep that knits up the ravell'd sleave of care."

Today, physicians and specialists on sleep disorders assert that Shakespeare was right. Sleep provides nourishment. It allows us to rebuild our bodies and our brains.

It is evident that sleep is not related to death at all, but rather a state that is necessary for restoration. There is, in fact, much activity that goes on during sleep. Those of us who remember our dreams and discuss them in the morning can attest to that. Sleep researchers have discovered several stages of sleep from less active to more active, and dreams seem to occur during the more active stages.

Our dreams come from our own minds and refer to some combination of recent experiences, memories, desires or fears that are stored in our minds. If we awaken suddenly during the dream stage of sleep, we can usually recall the dream or at least some phase of it. If it has some obvious relevance to our lives, we will recall it more vividly.

Sleep researchers have concluded that dreaming gives us an opportunity to reflect or analyze past problems or current facts that we have not yet seen resolved.

Most of us have had dreams in which we cannot remember our high school locker combination, are involved in some dramatic chase sequence that is life threatening, or recreate an intensive day's activities in irritating detail. Even though such dreams may not be a snap to interpret, they provide fascinating glimpses into the mind at work.

Although some people claim to need little or no sleep, researchers have been unable to find anyone who needed less than three or four hours a night. It seems safe to say that some of us need as little as five or six hours at night, while others require nine or ten hours. The average works out to be around seven.

Interestingly enough, the people who need little sleep also sleep the same on Sundays, apparently needing no catch-up. What is obvious to anyone is that the unexpected loss of an entire night's sleep can be devastating, at least psychologically. Although physically most of us can recover quite well from such a loss, we usually feel miserable. We know that we have been deprived of something that is necessary to our well-being.

What is most interesting to me is that people who lead active, busy daytime lives are usually able to secure a solid night's sleep as well. In other words, they sleep the same as they live - with great energy.

Except for occasional bouts with insomnia, there seems to be no way for most of us to avoid sleeping a third of our lives away. I have to admit that stretching out after a strenuous day under an electric blanket and a comforter always seems welcome. I just hope I'm not missing something.