Family matters
Some cosmology from book 7 of GE Hong 葛洪's Baopuzi 抱朴子:
The common folk see the heavens and the earth as big, and the myriad creatures as little, and therefore say: "Heaven and earth are the father and mother of the myriad creatures, and the myriad creatures are the children and grandchildren of heaven and earth."
If lice appear upon me, was it I who created them? Even if lice don't appear other than on upon me*, I am not their father or their mother, and they are not my children or my grandchildren. Potato bugs thrive in vinegar, mushrooms are grow on wood and stone, dung beetles gather in muddy water, green ivy flourishes on pine branches, but none are created by those environments. Does the way the myriad things gather in the gap between heaven and earth differ?
In heaven, there is the sun and the moon, heat and cold; in people, there is vision and breath. People can see what is far and liken it to what is near, compare this to that, but they don't know why their bodies grow old or stay youthful, ache or itch; similarly, heaven doesn't know why things gather or disperse, suffer or prosper. People can't make their eyes and ears stay sharp forever, or keep their energies from dwindling; similarly, heaven can't prevent solar or lunar eclipses, or cycle through the four seasons smoothly every year.
Functionally, this passage is an argument that although the universe is a necessary context for its denizens, it does not create them in any meaningful sense of the word. (You will not be surprised to learn that Ge Hong elsewhere uses the term 自然 to describe this concept of spontaneity and self-organization as opposed to reliance on an external creator.)
The details of the argument, though, are deliciously brutal. That humans, and everything else in the world, are not created and cherished by the universe, that's one idea. That we are actually more like lice, mushrooms, and dung beetles—a colony of parasites accumulating in "the gap between heaven and earth" (天地之間)—is quite another.
You can look at it another way, too: yeah, we're like beetles and fungus, but that's great, because it's all part of the ancient aleatory symphony we call evolution. Or, like the famous passage from Laozi says: 人法地, 地法天, 天法道, 道法自然. "People conform to the earth, the earth conforms to the heavens, the heavens conform to the Way, the Way is self-organizing."
無名酒:
Vaguely I remember that 自然 is a Buddhist concept, and not really analogous to our modern 自然 in some way (and should be read じぜん I think? You'd think I'd be more up to date on this.)
Ge Hong definitely wasn't the first to come up with the "Man, Heaven doesn't care about you" argument. But now I'm wondering if I need to be looking more at Daoism than just at the "skeptic" Confucianist traditions for that sort of thing.