From The Information, by Gleick:
Also in this secret paper, almost in passing, Shannon used a phrase he had never used before: “information theory.”
First Shannon had to eradicate “meaning.” The germicidal quotation marks were his. “The ‘meaning’ of a message is generally irrelevant,” he proposed cheerfully.
He offered this provocation in order to make his purpose utterly clear. Shannon needed, if he were to create a theory, to hijack the word information. “‘Information’ here,” he wrote, “although related to the everyday meaning of the word, should not be confused with it.”
Where a layman might have said that the fundamental problem of communication is to make oneself understood—to convey meaning—Shannon set the stage differently:
The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point.
“Point”was a carefully chosen word: the origin and destination of a message could be separated in space or in time; information storage, as in a phonograph record, counts as a communication. Meanwhile, the message is not created; it is selected. It is a choice. It might be a card dealt from a deck, or three decimal digits chosen from the thousand possibilities, or a combination of words from a fixed code book.
He could hardly overlook meaning altogether, so he dressed it with a scientist’s definition and then showed it the door:
Frequently the messages have meaning; that is they refer to or are correlated according to some system with certain physical or conceptual entities. These semantic aspects of communication are irrelevant to the engineering problem.
Nonetheless, as Weaver took pains to explain, this was not a narrow view of communication. On the contrary, it was all-encompassing: “not only written and oral speech, but also music, the pictorial arts, the theatre, the ballet, and in fact all human behavior.” Nonhuman as well: why should machines not have messages to send?