I have found a pattern: when people consider an idea in isolation, they tend to make good decisions. When they consider an idea a symbol of a vast overarching narrative, they tend to make very bad decisions.

If I recall correctly, these are generally called Grand Narratives. And it is one of the agendas of post-modern philosophy to try to undermine and eliminate them in favor of more nuanced ways of thinking about things.

Admittedly, most "po-mo" folks aren't as selective as we'd like, since they, often, consider rationality one example of a Grand Narrative.