Hi, Talia,

Yes, suddenly you are everywhere I look. :)

I fixed the link. Thanks for the alert. Try it again. You will find my approach is unique. Most approaches are spiritually oriented. Mine is just for health.

Yes, Mark is a great guy and his tiny house and family are fun. It's an honor to be his friend. You seem really nice, yourself. :)

Nature's rule. That's a great way to put it. The original human habitat is the floor of a rainforest, which is perfectly dark at night from the dense canopy. So yes, total darkness at night is natural and necessary for proper sleep. Jungles are notoriously noisy, but caves are silent, and I assume that people used caves for retreats in the past.

20 days is not a rule. But 8 or at least 4 days for a first or second retreat is a rule. In these short retreats, you will get a sense of how long your medium-length (less than a month) retreat should be.

Glad to see you are here on Steemit, too. I'll read your blog.

Cheers,
Andrew