3. Easy numbers: Shakespeare and the definition of information
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So far I have been using the term information theory to refer to a field of study—but what exactly is the theory to which some humanities scholars have objected so categorically when applied to cultural texts? This section briefly summarizes that theory in its classical form, Claude Shannon’s communications model as outlined by Warren Weaver’s landmark essay, “The Mathematics of Communication.” The model describes how a message travels from an information source to its destination, and how any changes resulting from the intervention of noise are subject to laws of probability. The components of the communications model, in sequence, are the information source, transmitter, channel, receiver, and destination (see Figure 1).
As Weaver summarizes the theory, “The information source selects a desired message out of a set of possible messages. […] The transmitter changes [encodes] this message into a signal which is sent over the communication channel to the receiver,” at which point a reverse process takes place in which “The receiver is a sort of inverse transmitter, changing the transmitted signal back into a message, and handing this message on to the destination.” The process as stated may seem simple enough, but information theory identifies two areas where complexity intervenes. One is the communication channel, where the signal may change in ways the information source did not intend: “These unwanted additions [to the signal] may be distortions of sound (in telephony, for example), or static (in radio), […] or errors in transmission (telegraphy or facsimile). All these changes in the signal may be called noise.” In this sense, the common phrase signal-to-noise ratio is relatively unimportant within the communications model since noise is part of signal; the distinction that matters is between message and noise.
¶ 2 Leave a comment on paragraph 2 0 A Shakespearean example may help both to illustrate and complicate the model. Mark Twain, in his anti-Stratfordian excursus Is Shakespeare Dead?, recounts how one Captain Ealer of the riverboat Pennsylvania (with whom Twain apprenticed in his youth) would recite Shakespeare from memory in the wheelhouse, interlaced with running commentary on Twain’s helmsmanship such that “if we were in a risky and difficult piece of river an ignorant person couldn’t have told, sometimes, which observations were Shakespeare’s and which were Ealer’s.” Twain gives an example of two mixed messages, each functioning as noise to the other:
¶ 3 Leave a comment on paragraph 3 2 What man dare, I dare!
Approach thou what are you laying in the leads for? what a hell of an idea! like the rugged ease her off a little, ease her off! rugged Russian bear, the armed rhinoceros or the there she goes! meet her, meet her! didn’t you know she’d smell the reef if you crowded it like that? Hyrcan tiger; take any shape but that and my firm nerves she’ll be in the woods the first you know! stop the starboard! … Now then, you’re all right; come ahead on the starboard; straighten up and go `long, never tremble: or be alive again, and dare me to the desert damnation can’t you keep her away from that greasy water? pull her down! snatch her! snatch her baldheaded! with thy sword; if trembling I inhabit then, lay in the leads!—no, only the starboard one, leave the other alone, protest me the baby of a girl. Hence horrible shadow! eight bells—that watchman’s asleep again, I reckon, go down and call Brown yourself, unreal mockery, hence!
¶ 4 Leave a comment on paragraph 4 0 While Ealer fulfills Milton’s prophecy of readers who monumentalize Shakespeare through the deep impressions of memory, Twain himself falls short as the noise of the world intervenes; he laments, “it was a damage to me, because I have never since been able to read Shakespeare in a calm and sane way. I cannot rid it of his explosive interlardings, they break in everywhere […].” Twain’s story captures the core concerns of information theory, including the “damage” Twain experiences as a result of the tangled messages, and the command-and-control scenario as the wheelhouse crew (functioning as a single system) responds to results of its own actions (“ease her off!”; “there she goes!”).
¶ 5 Leave a comment on paragraph 5 1 The Babel persisting in Twain’s memory is an example of the Shakespeare text assimilating itself to the condition of information, and its comic effect depends upon the reader’s impulse to disentangle the recognizably Shakespearean language—an impulse repeatedly frustrated by the ease with which the one message slips into the other, aided by the imperative phrasing which makes Twain himself into the ghost of Banquo by the end (“go down and call Brown yourself, unreal mockery, hence!”). The reader of this passage cannot help but relive the eternal dilemma of the Shakespeare editor, compounded by Twain’s implicit expectation that the original text of Macbeth should be deeply impressed in the reader’s own memory. The whole text of the passage might be considered a signal, in Shannon’s terms, but whether the recollected text of Macbeth or the navigational instructions are message or noise depends on what one considers important—that is the crux of Twain’s joke. What we call noise may be only a function of competing intentions and agencies.
¶ 6 Leave a comment on paragraph 6 0 Another area of complexity, and perhaps the most counterintuitive aspect of information theory, is the definition of what the word information actually means. To be clear: information in information theory means something very different from what it does in most everyday use. In Shannon’s model, information is not a thing, nor a quality of things corresponding to meaning or truth or accuracy, but rather a measure of the disambiguation required to express an intelligible message. Gregory Bateson uses the example of writing systems to illustrate:
¶ 7 Leave a comment on paragraph 7 0 An event or object such as the letter K in a given position in the text of a message might have been any other of the limited set of twenty-six letters in the English language. The actual letter excludes […] twenty-five alternatives. In comparison with an English letter, a Chinese ideograph would have excluded several thousand alternatives. We say, therefore, that the Chinese ideograph carries more information than the letter.
¶ 8 Leave a comment on paragraph 8 0 As Weaver was often at pains to emphasize, “The concept of information applies not to the individual messages, as the concept of meaning would, but rather to the situation as a whole.” Information in this sense is thus a measurable quantity within a definable system, not an interpretive quality lurking within an individual text or artifact.