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Concept of the Week · Episode 5
A philosopher's way of saying that causes are almost always tangled. An INUS condition is an Insufficient but Necessary part of a set of conditions that is itself Unnecessary but Sufficient for the result. The spark alone did not cause the fire, and the fire could have started another way.
Where it comes from
J.L. Mackie, in his 1965 paper Causes and Conditions and later in The Cement of the Universe.
How Peter explained it on the show
INUS, from the philosopher J.L. Mackie, which is a formal way of saying that causes are almost always more tangled than they look. A fire needs a spark, but the spark could have been a match, a lighter or a dropped cigarette, and no single one of them is the whole story. It is a useful lens for everything from why a wildfire took hold to why the far right gains ground: there is rarely one simple cause, however much a headline wants there to be.
Why it mattered that week
Episode five started with the emergency alert and the wildfire risk behind it, then moved to public shaming and the death of Professor Jason Arday. INUS is the lens for both. A fire needs a spark, but the spark could have been a match, a lighter or a dropped cigarette, and no single one of them is the whole story. The same goes for why a pile-on takes hold or why the far right gains ground: there is rarely one simple cause, however much a headline wants there to be.
Hear it in context
Public shaming, an eclipse and Count Binface
Public shaming and the Arday tragedy, the awe of an eclipse, and Farage versus a bin, tied together by one idea: it is always more complicated than the headline.
Questions people ask
Insufficient, Necessary, Unnecessary, Sufficient. The match was insufficient on its own (it needed dry grass and wind), necessary within that particular set of circumstances, and that whole set was unnecessary (another set would also have done it) but sufficient once it came together.
Because headlines are built to name one cause, and the world does not work that way. Asking what else had to be true for this to happen is the fastest route out of a lazy explanation, and it pairs with the episode's Triple T: wait a second before you respond.
Other concepts from the series
Mirror neurons · Authenticity · Confirmation bias · Attribution theory · Variable ratio reinforcement · Role exit
About the series
Concept of the Week is a regular feature of Experience, the weekly podcast in which clinical psychologist Professor Peter Kinderman and communications expert Hilary Jeffs take the news apart to see what is driving it. Peter picks a psychological idea most of us have half-remembered wrong and explains what it actually shows. New episodes every Tuesday. Where to listen.