His brother, Dr Tzvi N. Harris, with his wife Shoshana, played a pivotal role in the understanding of the immune system and the development of modern immunology.

From 1949 until his death, Harris maintained a close relationship with Naomi Sager, director of the Linguistic String Project at New York University.

Although his first direction was as a Semiticist, with publications on Ugaritic, Phoenician, and Canaanite, and on the origins of the alphabet; and later on Hebrew, both classical and modern, he began teaching linguistic analysis at Penn in 1931.

It is widely believed[12] that Harris carried Bloomfieldian ideas of linguistic description to their extreme development: the investigation of discovery procedures[13] for phonemes and morphemes, based on the distributional properties of these units and of antecedent phonetic elements.

Recognizing the primacy of speaker perceptions of contrast enabled remarkable flexibility and creativity in Harris's linguistic analyses which others - without that improved foundation - labelled "game playing" and "hocus-pocus.

"[18] Henry Hoenigswald tells us that in the late 1940s and the 1950s Harris was viewed by his colleagues as a person exploring the consequences of pushing methodological principles right to the edge.

But it was not false modesty that made Harris downplay his particular role in bringing about results, so much as a fundamental belief in the objectivity of the methods employed.

Given a representation in which contrasting utterances (non-repetitions) are written differently, even a conventional alphabetic orthography, stochastic procedures amenable to statistical learning theory identify the boundaries of words and morphemes.

[27] The overriding aim of the book, and the import of the word "methods" in its original title, is a detailed specification of validation criteria for linguistic analysis.

"[31] Harris's treatment of these as tools of analysis rather than theories of language, and his way of using them to work toward an optimal presentation for this purpose or that, contributed to the perception that he was engaged in "hocus-pocus" with no expectation that there was any absolute truth to the matter.

Harris's central methodological concern beginning with his earliest publications was to avoid obscuring the essential characteristics of language behind unacknowledged presuppositions, such as are inherent in conventions of notation or presentation.

[33][34] The basis of this methodological concern was that unacknowledged presuppositions, such as are inherent in conventions of notation or presentation, are dependent upon prior knowledge of and use of language.

Harris argued, following Sapir and Bloomfield, that semantics is included in grammar, not separate from it, form and information being two faces of the same coin.

A sequence or ntuple of word classes (plus invariant morphemes, termed constants) specifies a subset of sentences that are formally alike.

In linear algebra, a mapping that preserves a specified property is called a transformation, and that is the sense in which Harris introduced the term into linguistics.

One form in which this is exemplified is in the lexicon-grammar work of Maurice Gross and his colleagues [51] This relation of progressive refinement was subsequently shown in a more direct and straightforward way in a grammar of substring combinability resulting from string analysis (Harris 1962).

Their capacity to generate language-like formal systems was beginning to be employed in the design of computing machines, such as ENIAC, which was announced at Penn with great fanfare as a "giant brain" in 1946.

[53][54] Inter-word dependencies suffice to determine transformations (mappings in the set of sentences), and many generalizations that seem of importance in the various theories employing abstract syntax trees, such as island phenomena, fall out naturally from Harris's analysis with no special explanation needed.

[55][56] "In practice, linguists take unnumbered short cuts and intuitive or heuristic guess, and keep many problems about a particular language before them at the same time".

Harris factored the set of transformations into elementary sentence-differences, which could then be employed as operations in generative processes for decomposing or synthesizing sentences.

Harris's linguistic work culminated in the companion books A Grammar of English on Mathematical Principles (1982) and A Theory of Language and Information (1991).

In the latter work, also, Harris ventured to propose at last what might be the "truth of the matter" about the nature of language, what is required to learn it, its origin, and its possible future development.

His discoveries vindicate Sapir's recognition, long disregarded, that language is pre-eminently a social artifact, the users of which collectively create and re-create it in the course of using it.

The Medical Language Processor developed by Naomi Sager and others in the Linguistic String Program in the Courant Institute of Mathematical Sciences (NYU) has been made available on SourceForge.

Richard Kittredge and his colleagues have developed systems for automatic generation of text from data, which are used for weather radio broadcasts and for production of reportage of stock market activity, sports results, and the like.

[67] Harris's students in linguistics include, among many others, Joseph Applegate, Ernest Bender, Noam Chomsky, William Evan, Lila R. Gleitman, Michael Gottfried, Maurice Gross, James Higginbotham, Stephen B. Johnson, Aravind Joshi, Michael Kac, Edward Keenan, Daythal Kendall, Richard Kittredge, James A. Loriot/Lauriault, Leigh Lisker, Fred Lukoff, Paul Mattick Jr., James Munz, Bruce E. Nevin, Jean-Pierre Paillet, Thomas Pynchon, Ellen Prince, John R. Ross, Naomi Sager, Morris Salkoff, Thomas A. Ryckman, and William C. Watt.

In it, he claims that capitalism abandons those personal and social needs which are unprofitable, that cooperative arrangements arise for meeting those needs, that participants in these niches gain experience in forms of mutual aid which are crucial to survival in 'primitive' societies but which have been suppressed where they are inconvenient for the requirements of capitalist and that these should be fostered as seed points from which a more humane successor to capitalism can arise.

[69] This book, whose manuscript Harris had titled "Directing Social Change,’’ was brought to publication in 1997 by Seymour Melman, Murray Eden,[70] and Bill Evan.

From the early 1940s he and an informal group of fellow scientists in diverse fields collaborated on an extensive project called "A Frame of Reference for Social Change."

They developed new concepts and vocabulary on grounds that the existing ones of economics and sociology presuppose and thereby covertly perpetuate capitalist constructs, and that it is necessary to 'unfool' oneself before proceeding.