> It is not man's duty, as a matter of course, to devote himself to the eradication of any wrong; he may still properly have other concerns to engage him; but it is his duty, at least, to wash his hands of it, and, if he gives it no thought longer, not to give it practically his support.

Classic appeal to authority. The above quotation contains grand declarations with no supporting logic or evidence. Just because Henry David Thoreau said it doesn't make it true.

> in the real world you don't remotely get clean problem statements at all, let alone clean outcomes. Not only are the outcomes profoundly unknowable, but the world is full of other people pulling their own levers!

The outcomes of inaction are equally as "profoundly unknowable" as the outcomes of taking action. From an "unintended consequences" perspective, it's a wash. So we might as well focus on the first order known consequences, which are pretty clear.

If we're going down the road of appealing to authority, I'm partial to "The only thing necessary for the triumph of evil is for good men to do nothing"