A NOTE BY THE EDITORS [xi] To the reader of this somewhat unusual document, a few words of explanation, and caution. This is not a book in the usual sense, nor the well-rounded transcript of a symposium. These pages should rather be received as the partial account of conversa- tions within a group, a group whose interchange actually extends beyond the confines of the two day meeting reported herein. This account attempts to capture a fragment of the group interchange in all its evanescence, because it represents to us one of the few concerted efforts at interdisciplinary communication. The members of this group share the belief that one can and must attempt commu- nication across the boundaries, and often chasms, which separate the various sciences. The participants have come from many fields; they are physicists, mathematicians, electrical engineers, physiologists, neurologists, experimental psychologists, psychia- trists, sociologists, and cultural anthropologists. That such a gathering failed to produce the Babylonian confusion that might have been expected is probably the most remark- able result of this meeting and of those which preceded it. This ability to remain in touch with each other, to sustain the dialogue across departmental boundaries and, in particular, across the gulf between natural and social sciences is due to the unifying effect of certain key problems with which all members are concerned: the problems of communication and of self-integrating mechanisms. Revolving around these concepts, the discussion was communication about commu- nication, necessarily obscure in places and for more than one reason. Yet the actual outcome was far more intelligible than one might think, so that the editors felt enjoined to reproduce the transcript as faithfully as possible. The social process, of which these transactions are an incomplete residue, was not a sequence of formal »papers« read by individual participants and punctuated by pre- pared discussion. With few exceptions people spoke freely and without notes. Unavoidably some speakers produced inaccurate memories of their own facts, or of those of others, and trends of thought were often left incomplete. The printed record preserves the essential nature of this interchange in which partial associations were per- mitted on the assumption that closure would take place, at some other time, producing new ideas or reinforcing those that were thought of in passing. Stimulation, for many scientists, comes from such partial, and sometimes even inac- curate, reproductions of material from widely separated fields, fields which seem dis- similar except for the logical structure of | their central problem. If the reader wishes a [xii] format statement of the work and point of view of individual participants, he will have to consult other sources. This can be done with ease since most of the contributors have provided references to previously published material. The reader should be warned that the presentations and discussion tend to be responsive to previous meetings of the group. Some statements were designed to answer questions asked months or years before, or designed to evoke some long-anti- cipated answer from a fellow member. Radical changes in the manuscript would have been necessary had we attempted to rid the group of its history. Such changes would have been distortions, and would prevent the reader from noticing the unfinished state of the group’s affairs. Our editorial procedure, nevertheless, involved some revision of the transcript prior to publication. A verbatim record based on the stenotyped protocol, even if perfect, would in fact have been an incomplete and misleading account. It would have given the verbal content, but the tones of voice, the gestures, the attention directed by the turn of head toward one person or another would all be missing. For this reason, we adopted a more traditional procedure. Each participant was supplied with a mimeo- 342 CYBERNETICS 1951 graphed copy of his transcribed remarks, and was given the chance to revise his mate- rial for the sake of clarity and coherence. Not all of the participants availed themselves of this opportunity so that our working copy represented a mixture of revised and unrevised contributions. In the unrevised passages the editors corrected only those statements which seemed to them obvious errors in recording. For the rest, they con- fined their censorial activities to occasional deletions of overlapping or repetitive pas- sages and of a few all-too-cryptic digressions. Most of the asides, such as jokes or acid- ities, were preserved as long as they seemed intelligible to people outside the group. The editors were eager to retain the participants’ first names in the printed record when they had been used during the discussion, but this would have been an unneces- sary handicap to the reader. However, the reader should realize that most speakers addressed each other informally as a consequence of acquaintance outside the frame- work of these particular meetings. The occasional shifts to more formal modes of addressing each other was therefore indicative of distance and sometimes of disagree- ment. The use of last names also underscored the special role of the invited guests and of the subtle differences in pace and tone which some of them introduced into the meeting. It is noteworthy that these invited guests cannot be identified by any obvious differ- ences between their vocabulary and that of the regular members. One of the most sur- [xiii] prising features of the group is the | almost complete absence of an idiosyncratic vocabulary. In spite of their six years of association, these twenty-five people have not developed any rigid, in-group language of their own. Our idioms are limited to a handful of terms borrowed from each other: analogical and digital devices, feedback and servomechanisms, and circular causal processes. Even these terms are used only with diffidence by most of the members, and a philologist given to word-frequency counts might discover that the originators of »cybernetics« use less of its lingo than do their more recent followers. The scarcity of jargon may perhaps be a sign of genuine effort to learn the language of other disciplines, or it may be that the common point of view provided sufficient basis for group coherence. This common ground covered more than the mere belief in the worthwhileness of interdisciplinary discussion. All of the members have an interest in certain conceptual models which they consider potentially applicable to problems in many sciences. The concepts suggest a similar approach in widely diverse situations; by agreeing on the usefulness of these models, we get glimpses of a new lingua franca of science, fragments of a common tongue likely to counteract some of the confusion and complexity of our language. Chief among these conceptual models are those supplied by the theory of informa- tion.1, 2, 3 This theory has arisen under the pressure of engineering needs; the efficient design of electronic communication devices (telephone, radio, radar, and television) depended on achieving favorable »signal-to-noise ratios.« Application of mathematical tools to these problems had to wait for an adequate formulation of »Information« as contrasted to »noise.« If noise is defined as random activity, then information can be considered as order wrenched from disorder, as improbable structure in contrast to the greater probability of randomness. With the concept of entropy, classical thermodynamics expressed the 1 Shannon, C. E.: A mathematical theory of communication. Bell System. Tech. J. 27, 379-423 and 623- 656 (1948). 2 Shannon, C. E., and Weaver, W.: The Mathematical Theory of Communication. Urbana: University of Illinois Press, 1949 (p. 116). 3 Wiener, N.: Cybernetics or Control and Communication in the Animal and the Machine, New York: Wiley, 1948 (p. 194). A NOTE BY THE EDITORS 343 universal trend toward more probable states: any physiochemical change tending to produce a more nearly random distribution of particles. Information can thus be for- mulated as negative entropy, and a precise measure of certain classes of information can be found by referring to degrees of improbability of a state. The improbable distribution of slots in a slotted card, or the improbable arrange- ment of nucleic acids in the highly specific pattern of a | gene both can be considered [xiv] as »coded« information, the one decoded in the course of a technical (cultural) process, the other in the course of embryogeny. In both instances, that of the slotted card and that of the gene, we are faced not only with carriers of information but with powerful mechanisms of control: the slotted card can control long series of processes in a plant (without itself furnishing any of the requisite energy); the gene, as an organic template, somehow provides for its own reproduction and governs the building of a multicellular organism from a single cell. In the latter case, mere rearrangement of submicroscopic particles can apparently lead to mutations, improving or corrupting the organism’s plans as the case may be. Such rearrangement may indeed be similar to the difference brought about by the transposing of digits in numbers, 724 to 472, or by transposing letters in words such as art and rat.4 Extension of information theory to problems of language structure has been fur- thered by psychologists and statisticians.5, 6, 7, 8, 9 There are unexploited opportunities for additional applications of the theory in comparative linguistics, and more particu- larly in studies of the pathology of language. Yet available work is sufficient to show how communication considered from this standpoint can be investigated in mechani- cal systems, in organisms, in social groups;10 and the logical and mathematical prob- lems that go into the construction of modern automata, in particular the large elec- tronic computers,11 have at least partial application to our theorizing about nervous systems and social interactions.