Thoughts on inquiries in physical and inner worlds

摘要

It is estimated that recognizable human form appeared around 250,000 years ago however, not until 3000 BC, well-developed human settlements were established in Asia and the Middle East. On a clear night, the sky may appear studied with stars, but actually only around 6000-7000 stars, both the hemispheres put together, are visible to the naked eye. Recognizing that at any instant only half of them are above the horizon, and those near the horizon have poor visibility, it is safe to say that one is lucky to see more than 2000 stars at any one time.