The Jingle-Jangle Fallacy
The jingle-jangle fallacy names two errors that share a shape. Jingle is assuming that two measures carrying the same name are measuring the same thing. Jangle is assuming that two nearly identical things must be different because someone gave them different labels. Together they make the cheapest screening question anyone can ask of a new construct: is this actually new, or is it an old thing wearing a new word? It is a method for interrogating constructs rather than a testable effect.
What it is
The test costs nothing to apply and it disqualifies a startling amount of what gets sold as discovery. It is also the first gate, ahead of incremental validity: jingle-jangle asks whether a concept is new, and incremental validity asks whether it earns its keep. A construct has to survive both, and most survive neither.
The example Adrian Furnham reaches for is emotional intelligence, offered as a joke rather than as an argument: an earlier generation called the same ground social skills, and the one before that called it charm. Three labels, one neighbourhood, and only one of them comes with a test you can buy.
The stronger instance comes from inside a literature rather than from outside it. Chapter 11 of the same book quotes Kowalski and colleagues from 2021 approvingly and at length on the proliferation of dark traits, which is a jangle critique written by researchers who work in that field. When the complaint is coming from the people building the scales, it is worth more than any outside commentary.
Attribution has to be handled by declaration. The source supplies the concept, both halves of the definition, and the example, and supplies no originator, no year and no citation for the fallacy itself. This publication's own identification, offered as an identification and not a citation, traces jingle conventionally to Edward Thorndike in 1904 and jangle to Truman Kelley in 1927. Neither name appears in the book, in the prose or in the bibliography. Treat that pairing as a lead to verify rather than as a reference to reuse.