Well, those are the conventional takes that I'm taking issue with.

Conventional wisdom is a useful foil for novel thinking, but it's still usually right.

But how do we know society isn't like an insane asylum surrounded by universal truths which the inmates can't digest without losing their treasured insanity?

"Knowing" is way over-rated. All we have are probabilities, and we play them as we see them. I don't see much chance that we are unaware of morally relevant universal truths. For one thing, I'm not sure there are "universal" truths. There are, perhaps, propositions that have, so far, been true always and everywhere, but that's not the same thing. Morality on the day the world ends may be different from what it was on the day it began.

Why isn't the goal of social peace arbitrary and absurd, given the universe's indifference to our survival?

It's not arbitrary; nature has selected for it. Nature's "indifference" is no different from my desk's indifference. It's a non-concept.

Subjectively, the goal isn't arbitrary because it's motivated, but objectively our goals are futile, myopic, and laughable, if only because death's inevitability turns us into clowns, regardless of what we do in life.

A tale told by an idiot, full of sound and fury signifying nothing? Nature created self-esteem to deal with the insignificance of our lives to anyone or anything else. Morality and self-esteem work together to create an optimal "human environment," by which I mean an environment in which other humans are an important presence.

So yes, knowledge helps us act in moral ways. But knowledge also undermines the self-confidence or hubris needed to motivate and to justify the entire social endeavor.

Every silver lining has a cloud. As the Spanish say, there is no rose without a thorn. I think the morality side of the scale is heavier than the "undermine" side of the scale.

Surely, it's natural causality and thus overwhelming creativity (and destruction) of the universal plenum (of molecules, galaxies, and so on).

I think "creativity" anthropomorphizes. Maybe that's semantics, but there's a connotation there that I don't believe can be attached to non-purposeful action.

Why shouldn't a simplified form of aesthetics carry over, then, to the objective scientific explanation of natural causality/creativity?

Same answer. No one or thing "creates" a beautiful sunset. Beautiful sunsets just are, and they are beautiful because natural selection has caused us to see them as beautiful, perhaps as a by-product (I forget the fancy word for it) of our having an aesthetic sense.

Lawyers learn in torts class that there is no such thing as "negligence in the air." Actionable negligence is the breach of a duty to someone. You don't owe it to anyone to be careful per se. Rather, you owe it to those who may be injured as a proximate result of your carelessness not to be careless in a way that may foreseeably lead to their proximate injury. I would argue that there is no such thing as "beauty in the air"; it is a reification of a human reaction to stimulus.

Here, then, with a form of pantheism, we have an objective basis of enlightened values even after the death of God which arguably makes nonsense of the traditional moral discourses.

Well, you know my take on that. As a source of morality, metaphysics of any sort is just a TL;DR for game theory. Erasing God is like erasing the spots on the bowling alley that the good bowlers use to guide their rolls. The pins remain where they have always been. Only the algorithm changes.

I'll confess that I don't understand what pantheism brings to the table beyond a way to claim spirituality without deities, a nice trick, but, in my view, a trick nonetheless.