The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information

Miller, George (1956) The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information. [Journal (Paginated)]

Full text available as:

[img] HTML


First, the span of absolute judgment and the span of immediate memory impose severe limitations on the amount of information that we are able to receive, process, and remember. By organizing the stimulus input simultaneously into several dimensions and successively into a sequence or chunks, we manage to break (or at least stretch) this informational bottleneck. Second, the process of recoding is a very important one in human psychology and deserves much more explicit attention than it has received. In particular, the kind of linguistic recoding that people do seems to me to be the very lifeblood of the thought processes. Recoding procedures are a constant concern to clinicians, social psychologists, linguists, and anthropologists and yet, probably because recoding is less accessible to experimental manipulation than nonsense syllables or T mazes, the traditional experimental psychologist has contributed little or nothing to their analysis. Nevertheless, experimental techniques can be used, methods of recoding can be specified, behavioral indicants can be found. And I anticipate that we will find a very orderly set of relations describing what now seems an uncharted wilderness of individual differences. Third, the concepts and measures provided by the theory of information provide a quantitative way of getting at some of these questions. The theory provides us with a yardstick for calibrating our stimulus materials and for measuring the performance of our subjects. In the interests of communication I have suppressed the technical details of information measurement and have tried to express the ideas in more familiar terms; I hope this paraphrase will not lead you to think they are not useful in research. Informational concepts have already proved valuable in the study of discrimination and of language; they promise a great deal in the study of learning and memory; and it has even been proposed that they can be useful in the study of concept formation. A lot of questions that seemed fruitless twenty or thirty years ago may now be worth another look. In fact, I feel that my story here must stop just as it begins to get really interesting. And finally, what about the magical number seven? What about the seven wonders of the world, the seven seas, the seven deadly sins, the seven daughters of Atlas in the Pleiades, the seven ages of man, the seven levels of hell, the seven primary colors, the seven notes of the musical scale, and the seven days of the week? What about the seven-point rating scale, the seven categories for absolute judgment, the seven objects in the span of attention, and the seven digits in the span of immediate memory? For the present I propose to withhold judgment. Perhaps there is something deep and profound behind all these sevens, something just calling out for us to discover it. But I suspect that it is only a pernicious, Pythagorean coincidence.

Item Type:Journal (Paginated)
Additional Information:One of the 100 most influential papers in cognitive science:
Keywords:perception, cognition, discrimination, categorization, chunking, coding, memory, language, absolute judgment, relative judgment, information processing, information limits, resources, attention
Subjects:Psychology > Psychophysics
Psychology > Cognitive Psychology
Psychology > Perceptual Cognitive Psychology
ID Code:730
Deposited By: Harnad, Stevan
Deposited On:24 Jul 1998
Last Modified:11 Mar 2011 08:54

References in Article

Select the SEEK icon to attempt to find the referenced article. If it does not appear to be in cogprints you will be forwarded to the paracite service. Poorly formated references will probably not work.

1. Beebe-Center, J.G., Rogers, M.S., and O'Connell, D.N. Transmission of information about sucrose and saline solutions through the sense of taste. J. Psychol., 1955, 39, 157-160.

2. Bousfield, W.A., and Cohen, B.H. The occurrence of clustering in the recall of randomly arranged words of different frequencies-of-usage. J. Gen. Psychol., 1955, 52, 83-95.

3. Carmichael, L., Hogan, H.P., and Walter, A.A. An experimental study of the effect of language on the reproduction of visually perceived form. J. Exp. Psychol., 1932, 15, 73-86.

4. Chapman, D.W. Relative effects of determinate and indeterminate Aufgaben. Amer. J. Psychol., 1932, 44, 163-174.

5. Eriksen, C.W. Multidimensional stimulus differences and accuracy of discrimination. USAF, WADC Tech. Rep., 1954, No. 54-165.

6. Eriksen, C.W., and Hake, H.W. Absolute judgments as a function of the stimulus range and the number of stimulus and response categories. J. Exp. Psychol., 1955, 49, 323-332.

7. Garner, W.R. An informational analysis of absolute judgments of loudness. J. Exp. Psychol., 1953, 46, 373-380.

8. Hake, H.W., and Garner, W.R. The effect of presenting various numbers of discrete steps on scale reading accuracy. J. Exp. Psychol., 1951, 42, 358-366.

9. Halsey, R.M., and Chapanis, A. Chromaticity-confusion contours in a complex viewing situation. J. Opt. Soc. Amer., 1954, 44, 442-454.

10. Hayes, J.R.M. Memory span for several vocabularies as a function of vocabulary size. In Quarterly Progress Report, Cambridge, Mass.: Acoustics Laboratory, Massachusetts Institute of Technology, Jan.-June, 1952.

11. Jakobson, R., Fant, C.G.M., and Halle, M. Preliminaries to speech analysis. Cambridge, Mass.: Acoustics Laboratory, Massachusetts Institute of Technology, 1952. (Tech. Rep. No. 13.).

12. Kaufman, E.L., Lord, M.W., Reese, T.W., and Volkmann, J. The discrimination of visual number. Amer. J. Psychol., 1949, 62, 498-525.

13. Klemmer, E.T., and Frick, F.C. Assimilation of information from dot and matrix patterns. J. Exp. Psychol., 1953, 45, 15-19.

14. Külpe, O. Versuche über Abstraktion. Ber. ü. d. I Kongr. f. Exper. Psychol., 1904, 56-68.

15. Miller, G.A., and Nicely, P.E. An analysis of perceptual confusions among some English consonants. J. Acoust. Soc. Amer., 1955, 27, 338-352.

16. Pollack, I. The assimilation of sequentially encoded information. Amer. J. Psychol., 1953, 66, 421-435.

17. Pollack, I. The information of elementary auditory displays. J. Acoust. Soc. Amer., 1952, 24, 745-749.

18. Pollack, I. The information of elementary auditory displays. II. J. Acoust. Soc. Amer., 1953, 25, 765-769.

19. Pollack, I., and Ficks, L. Information of elementary multidimensional auditory displays. J. Acoust. Soc. Amer., 1954, 26, 155-158.

20. Woodworth, R.S. Experimental psychology. New York: Holt, 1938.


Repository Staff Only: item control page