What is the nonsense syllable?

Hermann Ebbinghaus, answered from the texts and cited to the page.

Hermann Ebbinghaus answers

The nonsense syllable is a controlled unit of memory material, constructed by placing a vowel sound between two consonants — drawn from the ordinary consonants of the alphabet and our eleven vowels and diphthongs.¹ From these combinations I built a stock of some 2,300 syllables, mixed together and drawn out by chance to form series of varying lengths, each series serving as the material for a test.²

The point of the construction is its deliberate emptiness of meaning. Ordinary material — poetry, prose, a striking phrase — brings with it associations, degrees of interest, prior knowledge, rhythm, beauty; all of this varies without regularity and confounds what one is trying to measure.³ Among many thousands of my syllable combinations, scarcely a few dozen carry any meaning at all, and of those only a fraction were noticed as meaningful during memorisation.⁴

What remains is something as nearly uniform and homogeneous as I could produce: each item equally new, equally indifferent, so that the work of forming and retaining a fresh association can be measured in its purity. I do not pretend the material is perfect. The syllables still engage sight, hearing, and the muscle sense of the organs of speech, and the series show surprising variation in how easily they are learned — variation not so different, as it turned out, from what one finds with meaningful verse.⁵

But the artificiality is the virtue, not the defect. One does not object to the physicist's frictionless plane that real roads have friction. Strip the confound, find the law in the pure case, and then restore the complications one by one. That is the method, and the nonsense syllable is its instrument.

Sources

1. a vowel sound being placed between two consonants... These syllables, about 2,300 in number, were mixed together and then drawn out by chance and used to construct series of different lengths.

   Memory A Contribution to Experimental Psychology

2. These syllables, about 2,300 in number, were mixed together and then drawn out by chance and used to construct series of different lengths, several of which each time formed the material for a test.

   Memory A Contribution to Experimental Psychology

3. In the case of the material nearest at hand, namely poetry or prose, the content is now narrative in style, now descriptive, or now reflective... There is thus brought into play a multiplicity of influences which change without regularity and are therefore disturbing.

   Memory A Contribution to Experimental Psychology

4. Among many thousand combinations there occur scarcely a few dozen that have a meaning and among these there are again only a few whose meaning was realised while they were being memorised.

   Memory A Contribution to Experimental Psychology

5. the homogeneity of the series of syllables falls considerably short of what might be expected of it. These series exhibit very important and almost incomprehensible variations as to the ease or difficulty with which they are learned.

   Memory A Contribution to Experimental Psychology