Hermann Ebbinghaus

Hermann Ebbinghaus (1850-1909) was a German psychologist and philosopher who is regarded as the pioneer of the experimental study of memory. Born in Barmen, in the Rhine Province of the Kingdom of Prussia, he belonged to a generation of late nineteenth-century thinkers who wanted to bring laboratory methods to the study of the mind. His lasting importance lies in showing that higher mental processes, not only sensations, could be measured and tested.

He began studying at Bonn at seventeen, initially planning to focus on history and philology, but his interest soon turned towards philosophy. The Franco-Prussian War interrupted his studies in 1870, and he served briefly in the Prussian army. In 1873 he received his doctorate with a dissertation on Eduard von Hartmann's philosophy of the unconscious. For the next few years he supported himself by tutoring in England and France. Legend has it that he found Gustav Fechner's Elements of Psychophysics in a London bookshop, and this book pointed him towards measuring the mind.

His central challenge was to apply experimental method to memory, which many of his contemporaries thought impossible, including Wilhelm Wundt, who believed higher faculties required other approaches. Ebbinghaus solved the problem by using nonsense syllables of consonant-vowel-consonant form, so that prior associations would not distort the results, and by making himself the only subject. He memorised lists to the beat of a metronome and counted the repetitions needed to recall them. One single investigation required some fifteen thousand recitations. He became a Dozent at the University of Berlin in 1880, and in 1885 he published his monumental study On Memory, which gathered his findings.

Among those findings are the forgetting curve, which shows a steep loss of learned material during the first hour and a levelling off after about a day; the learning curve; the serial position effect; and the savings effect, which shows that forgotten material still leaves a trace, because relearning a list takes less time than the first attempt. Ebbinghaus was aware of the limits of his design. Since he was his own sole participant, his conclusions were hard to generalise.

After the memory work he did not continue in that line. In 1890 he co-founded with Arthur König the journal Zeitschrift für Psychologie und Physiologie der Sinnesorgane. He held chairs in Berlin and Breslau, where he took part in a study of schoolchildren's mental ability, a forerunner of intelligence testing. In 1902 he published Fundamentals of Psychology, a textbook that was highly successful in Germany. He moved to Halle in 1905 and died there of pneumonia in 1909.

His influence remains strongest in cognitive psychology, where the forgetting curve and research on the spacing of practice are still standard references. His great achievement was to show that memory could be studied rigorously, opening a path that later researchers followed.