The concept of multiple discovery is the hypothesis that most scientific discoveries and inventions are made independently and more or less simultaneously by multiple scientists and inventors. The concept of multiple discovery opposes a traditional view—the "heroic theory" of invention and discovery.
When Nobel laureates are announced annually—especially in physics, chemistry, physiology-or-medicine, and economics—increasingly, in the given field, rather than just a single laureate, there are two or the maximally-permissible three, who often have independently made the same discovery.
Historians and sociologists have remarked on the occurrence, in science, of "multiple independent discovery". Robert K. Merton defined such "multiples" as instances in which similar discoveries are made by scientists working independently of each other. "Sometimes the discoveries are simultaneous or almost so; sometimes a scientist will make a new discovery which, unknown to him, somebody else has made years before."
Commonly cited examples of multiple independent discovery are the 17th-century independent formulation of calculus by Isaac Newton, Gottfried Wilhelm Leibniz and others, described by A. Rupert Hall; the 18th-century discovery of oxygen by Carl Wilhelm Scheele, Joseph Priestley, Antoine Lavoisier and others; and the theory of evolution of species, independently advanced in the 19th century by Charles Darwin and Alfred Russel Wallace.
Multiple independent discovery, however, is not limited to only a few historic instances involving giants of scientific research. Merton believed that it is multiple discoveries, rather than unique ones, that represent the common pattern in science.
Merton contrasted a "multiple" with a "singleton"—a discovery that has been made uniquely by a single scientist or group of scientists working together.
Sommer has introduced the term "nulltiple" to describe a scientific discovery that is suppressed or blocked from publication or dissemination via normal scientific channels. Nulltiple discoveries are often made serendipitously as part of an otherwise directed research program. As such, they are less likely to be re-discovered by others as is the case with many multiples. Sometimes nulltiples do eventually come to light, but often within circumstances of historical research rather than as a primary scientific disclosure.
Multiple discoveries in the history of science provide evidence for evolutionary models of science and technology, such as memetics (the study of self-replicating units of culture), evolutionary epistemology (which applies the concepts of biological evolution to study of the growth of human knowledge), and cultural selection theory (which studies sociological and cultural evolution in a Darwinian manner).
A recombinant-DNA-inspired "paradigm of paradigms" has been posited, that describes a mechanism of "recombinant conceptualization." This paradigm predicates that a new concept arises through the crossing of pre-existing concepts and facts. This is what is meant when one says that a scientist or artist has been "influenced by" another—etymologically, that a concept of the latter's has "flowed into" the mind of the former. Of course, not every new concept so formed will be viable: adapting social Darwinist Herbert Spencer's phrase, only the fittest concepts survive.
The same model, depicting innovation in science, technology, the social sciences, the humanities and the arts as arising from the combining of earlier-existing concepts, has also been described by Jonah Lehrer.
Multiple independent discovery and invention, like discovery and invention generally, have been fostered by the evolution of means of communication: roads, vehicles, sailing vessels, writing, printing, institutions of education, telegraphy, and mass media, including the internet. Gutenberg's invention of printing (which itself involved a number of discrete inventions) substantially facilitated the transition from the Middle Ages to modern times. All these developments have catalyzed and accelerated the process of recombinant conceptualization, and thus also of multiple independent discovery.
It has been argued that, in regard to multiple discovery, science and art are similar. When two scientists independently make the same discovery, their papers are not word-for-word identical, but the core ideas in the papers are the same. Likewise, two novelists may independently write novels with the same core themes, though their novels are not identical word-for-word.
The paradigm of recombinant conceptualization —more broadly, of recombinant occurrences—that explains multiple discovery in science and the arts, also elucidates the phenomenon of historic recurrence, wherein similar events are noted in the histories of countries widely separated in time and geography. It is the recurrence of patterns that lends a degree of prognostic power—and, thus, additional scientific validity—to the findings of history.
Discoverers understandably take pleasure in their accomplishments and generally seek to claim primacy to their discoveries. When it transpires that a discovery has multiple originators, they may either agree to share the credit or insist on their own exclusive primacy.
After Isaac Newton and Gottfried Wilhelm Leibniz had exchanged information on their respective systems of calculus in the 1670s, Newton in the first edition of his Principia (1687), in a scholium, apparently accepted Leibniz's independent discovery of calculus. In 1699, however, a Swiss mathematician suggested to Britain's Royal Society that Leibniz had borrowed his calculus from Newton. In 1705 Leibniz, in an anonymous review of Newton's Opticks, implied that Newton's fluxions (Newton's term for differential calculus) were an adaptation of Leibniz's calculus. In 1712 the Royal Society appointed a committee to examine the documents in question; the same year, the Society published a report, written by Newton himself, asserting his priority. Soon after Leibniz died in 1716, Newton denied that his own 1687 Principia scholium "allowed [Leibniz] the invention of the calculus differentialis independently of my own"; and the third edition of Newton's Principia (1726) omitted the tell-tale scholium. It is now accepted that Newton and Leibniz discovered calculus independently of each other.
In another classic case of multiple discovery, the two discoverers showed more civility. By June 1858 Charles Darwin had completed over two-thirds of his On the Origin of Species when he received a startling letter from a naturalist, Alfred Russel Wallace, 13 years his junior, with whom he had corresponded. The letter summarized Wallace's theory of natural selection, with conclusions identical to Darwin's own. Darwin turned for advice to his friend Charles Lyell, the foremost geologist of the day. Lyell proposed that Darwin and Wallace prepare a joint communication to the scientific community. Darwin being preoccupied with his mortally ill youngest son, Lyell enlisted Darwin's closest friend, Joseph Hooker, director of Kew Gardens, and together on 1 July 1858 they presented to the Linnean Society a joint paper that brought together Wallace's abstract with extracts from Darwin's earlier, 1844 essay on the subject. The paper was also published that year in the Society's journal. Neither the public reading of the joint paper nor its publication attracted the least interest; but Wallace, "admirably free from envy or jealousy," had been content to remain in Darwin's shadow.
"When the time is ripe for certain things, they appear at different places in the manner of violets coming to light in early spring."
— Farkas Bolyai, to his son Janos, urging him to claim the invention of non-Euclidean geometry without delay.
Quoted in Li & Vitanyi, An introduction to Kolmogorov Complexity and Its Applications, 1st ed., p. 83.
- Historic recurrence
- History of science
- Hundredth monkey effect
- List of multiple discoveries
- Matthew effect
- Stigler's law
- David Lamb and S.M. Easton, Multiple Discovery: The Pattern of Scientific Progress.
- Robert K. Merton, "Resistance to the Systematic Study of Multiple Discoveries in Science," European Journal of Sociology, 4:237–82, 1963. Reprinted in Robert K. Merton, The Sociology of Science: Theoretical and Empirical Investigations, Chicago, University of Chicago Press,1973, pp. 371–82. 
- Robert K. Merton, The Sociology of Science, 1973.
- A. Rupert Hall, Philosophers at War, New York, Cambridge University Press, 1980.
- Robert K. Merton, "Singletons and Multiples in Scientific Discovery: a Chapter in the Sociology of Science," Proceedings of the American Philosophical Society, 105: 470–86, 1961. Reprinted in Robert K. Merton, The Sociology of Science: Theoretical and Empirical Investigations, Chicago, University of Chicago Press, 1973, pp. 343–70.
- Robert K. Merton, On Social Structure and Science, p. 307.
- Toby J. Sommer, "Bahramdipity and Nulltiple Scientific Discoveries," Science and Engineering Ethics, 2001, 7(1), 77–104. Free PDF: http://www.bmartin.cc/dissent/documents/Sommer.pdf
- Harriet Zuckerman, Scientific Elite: Nobel Laureates in the United States, Free Press, 1979.
- Christopher Kasparek, "Prus' Pharaoh: the Creation of a Historical Novel," The Polish Review, vol. XXXIX, no. 1 (1994), pp. 45-46.
- Jonah Lehrer, Imagine: How Creativity Works, 2012.
- Lamb and Easton, Multiple Discovery, chapter 9: "Originality in art and science."
- Christopher Kasparek, "Prus' Pharaoh: the Creation of a Historical Novel," pp. 45-46.
- Kasparek had earlier written about recombinant conceptualization in his review of Robert Olby, The Path to the Double Helix (Seattle, University of Washington Press, 1974), in Zagadnienia naukoznawstwa (Logology, or Science of Science), Warsaw, vol. 14, no. 3 (1978), pp. 461-63. Cited in Christopher Kasparek, "Prus' Pharaoh: the Creation of a Historical Novel," pp. 45-46.
- Will and Ariel Durant, The Age of Louis XIV, pp. 532-34.
- Tori Reeve, Down House: the Home of Charles Darwin, pp. 40-41.
- Will and Ariel Durant, The Age of Louis XIV: A History of European Civilization in the Period of Pascal, Molière, Cromwell, Milton, Peter the Great, Newton, and Spinoza: 1648-1715 (The Story of Civilization: Part VIII), New York, Simon and Schuster, 1963.
- Christopher Kasparek, "Prus' Pharaoh: the Creation of a Historical Novel," The Polish Review, vol. XXXIX, no. 1 (1994), pp. 45–50.
- Christopher Kasparek, review of Robert Olby, The Path to the Double Helix (Seattle, University of Washington Press, 1974), in Zagadnienia naukoznawstwa (Logology, or Science of Science), Warsaw, vol. 14, no. 3 (1978), pp. 461–63.
- David Lamb and S.M. Easton, Multiple Discovery: The Pattern of Scientific Progress, Amersham, Avebury Press, 1984.
- Jonah Lehrer, Imagine: How Creativity Works, 2012, ISBN 9780547386072.
- Robert K. Merton, On Social Structure and Science, edited and with an introduction by Piotr Sztompka, University of Chicago Press, 1996.
- Robert K. Merton, The Sociology of Science: Theoretical and Empirical Investigations, Chicago, University of Chicago Press,1973.
- Tori Reeve, Down House: the Home of Charles Darwin, London, English Heritage, 2009.
- Harriet Zuckerman, Scientific Elite: Nobel Laureates in the United States, Free Press, 1979.
- Annals of Innovation: In the Air:Who says big ideas are rare?, Malcolm Gladwell, New Yorker, May 12, 2008
- The Technium: Simultaneous Invention, Kevin Kelly, May 9, 2008
- Apperceptual: The Heroic Theory of Scientific Development, Peter Turney, January 15, 2007