In 1938, within logically-inspired philosophy, the philosopher Charles W. Morris had conceived the extraordinarily ambitious program of a general theory of signs, or 'semiotics'. This theory was to encompass both linguistic and non-linguistic signs, human and animal signs. Published in November 2022, the book What it All Means, by Philippe Schlenker, Senior Research Fellow at Institut Jean-Nicod (UMR8129, CNRS / ENS-PSL) and Global Distinguished Professor at New York University, shows that contemporary formal linguistics, and especially semantics (the study of meaning), is on the verge of realizing this program, but within a scientific framework that did not exist in 1938.
While the term "semiotics" has been used by many fields of the humanities and social sciences to refer to the generalized study of meaning, the formal and experimental approach to meaning arose in a very different tradition. Specifically, in the 1960's and 1970's, well after Charles W. Morris's program was conceived, two "formalist" revolutions successively took place in linguistics. The first one, associated with the name of the linguist Noam Chomsky, consisted in treating human languages as formal languages with respect to their form or 'syntax', with both similarities and differences compared to the formal languages of mathematics and computer science. The second revolution, associated with the name of the logician Richard Montague, consisted in extending this program to semantics with the tools of 'model theory', a branch of logic that offered an explicit definition of truth. Following this second revolution, the key slogan of semantics was that "to understand the meaning of a sentence is to know under what conditions it can be true"; the theory of meaning thus became a theory of truth. In the 1980s and 1990s, these two programs were unified, with a growing integration with psycholinguistics and cognitive science. The result is a systematic theory of meaning in spoken languages, based on a theory of truth, and supported by formal and experimental methods.
It is only recently that the ambition of a general theory of meaning, associated with the term "semiotics", re-emerged in formal linguistics (often under the term "Super Semantics"). Semantics has now fully integrated signed languages (used by Deaf communities around the world), which have the same logical and grammatical structures as spoken languages but make more systematic use of iconicity (the process by which a sign resembles what it denotes). Even more recently, formal semantics has been extended to non-standard objects: gestures that co-occur with or sometimes replace speech, facial expressions, emojis; animal communication, especially in primates; and even music and dance. In all these cases, understanding the meaning of a representation is to know under what conditions it can be adequate or 'true'. Here too, the theory of truth lies at the heart of the theory of meaning.
The book What it All Means: Semantics for (Almost) Everything provides an introduction to the results and foundations of contemporary semantics in the context of this general theory of meaning. Its author, Philippe Schlenker, is a specialist of formal semantics who has worked on all aspects of meaning, from philosophical logic to formal semantics, from spoken to signed languages, from animal communication to gestures and music; he was awarded a Silver Medal of CNRS in 2021.
The book introduces to the main divisions of linguistics using the example of some primate languages, which are much less complex than human language. It then explores the main components of human meaning in both spoken and signed languages, using at several junctures the latter as a particularly illuminating guide. For example, linguists have postulated that unpronounced logical variables are crucial to understanding the sentence Sarkozy told Obama that he would win the election. This sentence is ambiguous: the pronoun he can refer to Sarkozy, or to Obama. Linguistics proposes that the sentence can be mentally represented in two ways: as Sarkozyx told Obamay that hex would win the election, with the same variable x on he and on Sarkozy; or as Sarkozyx told Obamay that hey would win the election, with the same variable y on he and on Obama. These variables are postulated on an indirect basis in spoken languages. But remarkably, they can be realized explicitly in sign languages. For instance, in French sign language (LSF), one can sign Sarkozy on the left and Obama on the right, and point to the left or to the right depending on whether one wants to obtain the reading he = Sarkozy or he = Obama. In this case, sign languages make visible the logical structure of language in general.
After giving an overview of the mechanisms of meaning production in spoken and signed languages, the book describes recent extensions of semantics to gestures, facial expressions, and even emojis. It then addresses the perennial question of the meaning of music, to which it offers a new answer: music has a systematic meaning, but produced by very different mechanisms from linguistic meaning, ones that are partly lifted from normal auditory cognition. As in the latter, a lower-frequency sound is associated with a larger object (which is why an elephant is better evoked by a double bass than by a flute); and a sound with an increasing loudness evokes an object that is gaining energy, or that is getting closer. With additional rules of the same type, one can obtain a systematic but particularly abstract (underspecified) meaning for music, which allows it to fit extremely diverse scenes (for example in films or cartoons).
Since semantics is based on a logical theory of truth, the book then turns to one of the most formidable challenges for this program: logical paradoxes, such as the Liar's paradox, "The present statement is false". This sentence is a paradox because it cannot, without contradiction, be assigned the value "true", nor the value "false". The book explains both the depth of the problem, and the very systematic answer developed by semantics, which consists in postulating an additional truth value ("neither true nor false").
The book closes with more general lessons for the scientific approach to the humanities. Grammar is its inspiration, and contemporary semantics is one of its most fruitful models.
(Deepl.com was consulted while preparing this translation.)
Schlenker P. 2022, What It All Means. Semantics for (Almost) Everything, MIT Press.