After my last post about the jingle fallacy, it is impossible to resist talking about the jangle fallacy.

In short, the jangle fallacy occurs when a person treats two concepts as being different because there are different words for them. The jangle fallacy occurs because “. . . psychologists can name more things than they can measure independently . . .” (Lubinski, 2004, p. 98).

If this definition sounds familiar, it is because the jangle fallacy is the exact opposite of the jingle fallacy. (In the jingle fallacy, two different concepts are treated as being the same because there is one word for both.) In fact, we can thank Kelley (1927) for both fallacies.

The classic example of the jangle fallacy is “aptitude tests” vs. “achievement tests.” Supposedly, aptitude tests are designed to measure an examinee’s future learning ability, while achievement tests are measures of past learning.

In practice, achievement and aptitude tests are highly correlated, and sometimes the same questions appear on both types of tests (Lohman, 2006). There is merely a convention to give the name “achievement test” to tests that measure material that students have already been taught and “aptitude test” when the test is being used to make predictions about future learning. Sometimes, the same test can serve each function, depending on whether the examinees have been exposed to the test content before (e.g., Warne et al., 2016).

There reason “aptitude” and “achievement” are so similar is that the best predictor of future learning is past learning in the same field. Therefore, an achievement test is a very good predictor of aptitude in the same field. There is no reason why the same test and/or questions cannot be used for both purposes.

Intelligence seems to be another concept particularly prone to the jangle fallacy, as shown by the multitudes of euphemisms for it: cognitive ability, general ability, educational aptitude, college success aptitude, etc. In Chapter 7 of my upcoming book, In the Know: Debunking 35 Myths About Human Intelligence (due in late 2020), I discuss how some researchers have inadvertently created intelligence tests because they thought they were measuring a trait that had a different name. But instead, they fell victim to the jangle fallacy and created an intelligence test.


Kelley, T. L. (1927). Interpretation of educational measurements. Yonkers-on-Hudson, NY: World Book Company.

Lohman, D. F. (2006). Beliefs about differences between ability and accomplishment: From folk theories to cognitive science. Roeper Review, 29(1), 32-40. doi: 10.1080/02783190609554382

Lubinski, D. (2004). Introduction to the special section on cognitive abilities: 100 years after Spearman’s (1904) “‘General intelligence,’ objectively determined and measured”. Journal of Personality and Social Psychology, 86, 96-111. doi: 10.1037/0022-3514.86.1.96

Warne, R. T., Doty, K. J., Malbica, A. M., Angeles, V. R., Innes, S., Hall, J., & Masterson-Nixon, K. (2016). Above-level test item functioning across examinee age groups. Journal of Psychoeducational Assessment, 34, 54-72. doi:10.1177/0734282915584851