Weaver had first mentioned the possibility of using digital computers to translate documents between natural human languages in March 1947 in a letter to the cyberneticist Norbert Wiener.
In the following two years, he had been urged by his colleagues at the Rockefeller Foundation to elaborate on his ideas. The result was a memorandum, entitled simply "Translation", which he wrote in July 1949 at Carlsbad, New Mexico.[3] Said to be probably the single most influential publication in the early days of machine translation, it formulated goals and methods before most people had any idea of what computers might be capable of, and was the direct stimulus for the beginnings of research first in the United States and then later, indirectly, throughout the world.
Weaver's memorandum was designed to suggest more fruitful methods than any simplistic word-for-word approach, which had grave limitations. He put forward four proposals.
The first was that the problem of multiple meanings might be tackled by the examination of immediate context. For example, the English word fast has at least two meanings which we can paraphrase as rapid or motionless. If we wish to translate an English text, it is likely that these two senses of fast correspond to different words in the target language, and in order to translate the word correctly one needs to know which sense is intended. Weaver proposed that this problem could be solved by looking at the words that occur in the vicinity of the word to be translated, and he conjectured that the number of context words that would be required is fairly small.
The second proposal in the memorandum was inspired by work on an early type of neural networks by McCulloch and Pitts. Weaver interpreted these results as meaning that given a set of premises, any logical conclusion could be deduced automatically by computer. To the extent that human language has a logical basis, Weaver hypothesized that translation could be addressed as a problem of formal logic, deducing "conclusions" in the target language from "premises" in the source language.
The third proposal was that cryptographic methods were possibly applicable to translation. If we want to translate, say, a Russian text into English, we can take the Russian original as an encrypted version of the English plaintext. Weaver was especially impressed with the potential of Claude Shannon's classified work on cryptography and Information theory from World War II.
Finally, the fourth proposal was that there may also be linguistic universals underlying all human languages which could be exploited to make the problem of translation more straightforward.
Weaver argued for this position with what is one of the best-known metaphors in the literature of machine translation: "Think, by analogy, of individuals living in a series of tall closed towers, all erected over a common foundation. When they try to communicate with one another, they shout back and forth, each from his own closed tower. It is difficult to make the sound penetrate even the nearest towers, and communication proceeds very poorly indeed. But, when an individual goes down his tower, he finds himself in a great open basement, common to all the towers. Here he establishes easy and useful communication with the persons who have also descended from their towers".
Wrote history of translations of Alice's Adventures in Wonderland📒]: Alice in many tongues: The translations of Alice in Wonderland📒
in 2015 new book: Alice in a World of Wonderlands📒