The standard version is that in looking at the stars we realize our own insignificance. Apart from the sheer non-sequitur from "of comparatively small dimensions" to "insignificant" (to whom?!), such tropes may serve as a sort of moral anaesthetic: "Taking the Hubble View, does it really, fundamentally matter if I steal money from my investors?"
The general problem is that of making leaps from empty empirical facts to (almost certainly mistaken or self-serving) moral conclusions.
I notice I am confused, and I do get a sense of insignificance/wonderment when looking at the night sky.
Are there actually people who use the size of the universe to justify moral nihilism?
Another month has passed and here is a new rationality quotes thread. The usual rules are: