If we think of the tangible, real, world as science does, as being made up of vibrating waves, fleeting particles, and forces that are merely ghost remnants, side effects of energetic actions of other dimensions we can't comprehend....then one has to question, is anything really tangible? In that context, your own thoughts may be just as tangible as the ground you stand.

People often ask if we are in a computer simulation, but they rarely ask if our whole world's eternity is just the fleeting thoughts, day dream, or lonely internal dialog of some higher being's conscious mind. Surely it is not a giant turtle.

It reminds me of a disturbing middle of the night animated short on PBS, where the odd people of a silly clay/stop-motion town realized they were just some guy's dream. Fearing he'd wake and they'd cease to exist, they devised a plan. They climed out of their slumbering god's head from his ear, while he slept, and proceeded to humorously strap pillows around his head, so the alarm clock would not wake him.

That show messed with my head as a teenager, when I saw it once 20-30 years ago, and here I go pondering it once again.