The Flynn Effect is the idea that human intelligence tests scores have supposedly been increasing at a substantial, sustained rate throughout the world. Studies that support this effect generally show that it is fluid intelligence (i.e. problem solving skills, reasoning, and learning ability) that shows much more significant gains compared to crystallized intelligence (i.e. learned information such as vocabulary or math). The effect is named after James R. Flynn, who promoted the theory.
There are many counterexamples to the Flynn Effect that indicate a rapid decline in human intelligence. The quality of music, news articles, online encyclopedias, personal letters, and debates are all noticeably decreasing. A number of studies conclude that the Flynn Effect either never existed, or that the increase in human intelligence has ended.
- Graham, Charles and Plucker, Jonathan. "The Flynn Effect." 2010. Indiana University. http://www.indiana.edu/~intell/flynneffect.shtml
- Shalizi, Cosma Rohilla. [Book review of What is Intelligence? by James R. Flynn.] 2009. http://www.cscs.umich.edu/~crshalizi/reviews/flynn-beyond/
- Sundet, J.; Barlaug, D.; Torjussen, T. 2004. Intelligence 32 (4), pp. 349–362.
- Teasdale TW & Owen DR. 2005. "A long-term rise and recent decline in intelligence test performance: The Flynn Effect in reverse". Personality and Individual Differences 39 (4), pp. 837–843.
- Lynn, R.; Harvey, J. 2008. "The decline of the world's IQ". Intelligence 36 (2), pp. 112.