And that goes back to when he was driving stage in the Yellowstone.
Casey was making the trip out, one time, and he had just one passenger because it was at the end of the season and there had been a week of nasty weather that had driven out most of the sightseers and no new ones were coming in.

This man was a peevish, egotistical sort, I imagine; at any rate he did a lot of talking about himself and his ill luck, and he told Casey of his misfortunes by the hour.
Casey did not mind that much.

He says he didn't listen half the time.

But finally the fellow began talking of the wealth that is wasted on folks who can't use it properly or even appreciate the good fortune.
To illustrate that point he told a story that set Casey's mind to seeing visions.

The man told about an old Indian who lived in dirt and a government blanket and drank bad whisky when he could get it, and whipped his squaw and behaved exactly like other Indians.