This is a Lexicon entry: the mechanism, when it shows up, and the countermeasure. The full correction, with real-world cases and the audit prompt, hasn't been written yet.
Definition
The tendency to attribute complex outcomes to a single cause, when in reality most events result from many causes conspiring together. Our minds cannot comfortably process webs of mutual causation so we reduce them to a single thread: "Social media caused depression." "Bad parenting caused crime." The single-cause story is always more compelling than the true multi-causal one - which is why it spreads further and misleads more.
When it shows up
Explaining social problems in public discourse (why crime rose, why teens are anxious, why a market crashed). Post-mortem analysis of a project failure. Reading popular non-fiction that offers one-variable theories of history or behaviour.
Failure mode
The other contributing causes become invisible the moment one candidate is named. Attention, policy and action collapse onto the single factor. The causal web keeps producing the effect while everyone argues about the one variable.
Countermeasure
Before acting on a single-cause story, list five other plausible contributing causes and rank them. If you cannot name five, the reductive collapse is still running.
Related traps
Also connected in the mapThe Fundamental Attribution Error·Hindsight Bias·The Narrative Fallacy·3 more, locked
Credit & first seen
PopularizedThe multi-causal critique has roots in philosophy of science (Mill, 1843) and systems thinking (Meadows, D. (2008). Thinking in Systems. Chelsea Green). This framing popularised by Gurwinder Bhogal in early Twitter threads (2020 - 2021) and across multiple posts at gurwinder.blog.
Read next
Entry #12 of 631 in The Lexicon · see the full Lexicon