Yes a period of approximately 2-3000 years each time. Thousands of years apart. Then aomething happened that covered the cave...something catastrophic perhaps. Perhaps man rises and falls over and over again in this planet. It’s a pet theory of mine based on the story “Nightfall” by Isaac Asimov.
I think you may be right, in a way. I haven’t read the book you reference, but maybe we’re just doing everything over and over again, in an ever upward, ever widening spiral.
-JT