When you turn off the lights before you go to bed... what happens? Do the things move in the dark, while you can't see them, because there's no light? What if

When you turn off the lights before you go to bed... what happens? Do the things move in the dark, while you can't see them, because there's no light? What if you didn't have eyes? What then? If tree falls in the forest, and no one is there to see it... does it make a sound?