Hermann Ebbinghaus (1850–1909) After earning his Ph.D. in philosophy in 1873, Ebbinghaus worked as a private tutor for several years. It was during this time that he conducted his famous research on the memory of nonsense syllables. In 1885, he published his results in Memory: A Contribution to Experimental Psychology. Ebbinghaus observed, “Left to itself, every mental content gradually loses its capacity for being revived. Facts crammed at examination time soon vanish, if they were not sufficiently grounded by other study and later subjected to a sufficient review.” Among his other notable contributions, he developed an early intelligence test, called the Ebbinghaus Completion Test (Lander, 1997).

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