Syntactic in the context of "Generative grammar"

Deductive reasoning is the process of drawing valid inferences. An inference is valid if its conclusion follows logically from its premises, meaning that it is impossible for the premises to be true and the conclusion to be false. For example, the inference from the premises "all men are mortal" and "Socrates is a man" to the conclusion "Socrates is mortal" is deductively valid. An argument is sound if it is valid and all its premises are true. One approach defines deduction in terms of the intentions of the author: they have to intend for the premises to offer deductive support to the conclusion. With the help of this modification, it is possible to distinguish valid from invalid deductive reasoning: it is invalid if the author's belief about the deductive support is false, but even invalid deductive reasoning is a form of deductive reasoning.

Deductive logic studies under what conditions an argument is valid. According to the semantic approach, an argument is valid if there is no possible interpretation of the argument whereby its premises are true and its conclusion is false. The syntactic approach, by contrast, focuses on rules of inference, that is, schemas of drawing a conclusion from a set of premises based only on their logical form. There are various rules of inference, such as modus ponens and modus tollens. Invalid deductive arguments, which do not follow a rule of inference, are called formal fallacies. Rules of inference are definitory rules and contrast with strategic rules, which specify what inferences one needs to draw in order to arrive at an intended conclusion.

Colloquialism (also called colloquial language, everyday language, or general parlance) is the linguistic style used for casual (informal) communication. It is the most common functional style of speech, the language normally employed in casual conversation and other informal contexts. Colloquialism is characterized by the frequent use of expressive phrases, idioms, anthropocentrism, and a lack of specialized focus, and has a rapidly changing lexicon. It can also be distinguished by its usage of formulations with incomplete logical and syntactic ordering.

A specific instance of such language is termed a colloquialism. The most common term used in dictionaries to label such an expression is colloquial.

In the study of the biological sciences, biocommunication is any specific type of communication within (intraspecific) or between (interspecific) species of plants, animals, fungi, protozoa and microorganisms. Communication means sign-mediated interactions following three levels of rules (syntactic, pragmatic and semantic). Signs in most cases are chemical molecules (semiochemicals), but also tactile, or as in animals also visual and auditive. Biocommunication of animals may include vocalizations (as between competing bird species), or pheromone production (as between various species of insects), chemical signals between plants and animals (as in tannin production used by vascular plants to warn away insects), and chemically mediated communication between plants and within plants.

Biocommunication of fungi demonstrates that mycelia communication integrates interspecific sign-mediated interactions between fungal organisms, soil bacteria and plant root cells without which plant nutrition could not be organized. Biocommunication of Ciliates identifies the various levels and motifs of communication in these unicellular eukaryotes. Biocommunication of Archaea represents key levels of sign-mediated interactions in the evolutionarily oldest akaryotes. Biocommunication of phages demonstrates that the most abundant living agents on this planet coordinate and organize by sign-mediated interactions. Biocommunication is the essential tool to coordinate behavior of various cell types of immune systems.

In linguistics, ellipsis (Ancient Greek: ἔλλειψις, romanized: élleipsis, lit. 'omission') or an elliptical construction is the omission from a clause of one or more words that are nevertheless understood in the context of the remaining elements. There are numerous distinct types of ellipsis acknowledged in theoretical syntax. Theoretical accounts of ellipsis seek to explain its syntactic and semantic factors, the means by which the elided elements are recovered, and the status of the elided elements.

In linguistics and the philosophy of language, a locutionary act is the performance of an utterance, and is one of the types of force, in addition to illocutionary act and perlocutionary act, typically cited in Speech Act Theory. Speech Act Theory is a subfield of pragmatics that explores how words and sentences are not only used to present information, but also to perform actions. As an utterance, a locutionary act is considered a performative, in which both the audience and the speaker must trust certain conditions about the speech act. These conditions are called felicity conditions and are divided into three different categories: the essential condition, the sincerity condition, and the preparatory condition.

The term equally refers to the surface meaning of an utterance because, according to J. L. Austin's posthumous How To Do Things With Words, a speech act should be analysed as a locutionary act (i.e. the actual utterance and its ostensible meaning, comprising phonetic, phatic, and rhetic acts corresponding to the verbal, syntactic, and semantic aspects of any meaningful utterance), as well as an illocutionary act (the semantic 'illocutionary force' of the utterance, thus its real, intended meaning), and in certain cases a further perlocutionary act (i.e. its actual effect, whether intended or not).

In deductive logic, a consistent theory is one that does not lead to a logical contradiction. A theory ${\displaystyle T}$ is consistent if there is no formula ${\displaystyle \varphi }$ such that both ${\displaystyle \varphi }$ and its negation ${\displaystyle \lnot \varphi }$ are elements of the set of consequences of ${\displaystyle T}$. Let ${\displaystyle A}$ be a set of closed sentences (informally "axioms") and ${\displaystyle \langle A\rangle }$ the set of closed sentences provable from ${\displaystyle A}$ under some (specified, possibly implicitly) formal deductive system. The set of axioms ${\displaystyle A}$ is consistent when there is no formula ${\displaystyle \varphi }$ such that ${\displaystyle \varphi \in \langle A\rangle }$ and ${\displaystyle \lnot \varphi \in \langle A\rangle }$. A trivial theory (i.e., one which proves every sentence in the language of the theory) is clearly inconsistent. Conversely, in an explosive formal system (e.g., classical or intuitionistic propositional or first-order logics) every inconsistent theory is trivial. Consistency of a theory is a syntactic notion, whose semantic counterpart is satisfiability. A theory is satisfiable if it has a model, i.e., there exists an interpretation under which all axioms in the theory are true. This is what consistent meant in traditional Aristotelian logic, although in contemporary mathematical logic the term satisfiable is used instead.

In a sound formal system, every satisfiable theory is consistent, but the converse does not hold. If there exists a deductive system for which these semantic and syntactic definitions are equivalent for any theory formulated in a particular deductive logic, the logic is called complete. The completeness of the propositional calculus was proved by Paul Bernays in 1918 and Emil Post in 1921, while the completeness of (first order) predicate calculus was proved by Kurt Gödel in 1930, and consistency proofs for arithmetics restricted with respect to the induction axiom schema were proved by Ackermann (1924), von Neumann (1927) and Herbrand (1931). Stronger logics, such as second-order logic, are not complete.

In linguistics, a grammatical construction is any syntactic string of words ranging from sentences over phrasal structures to certain complex lexemes, such as phrasal verbs.

Grammatical constructions form the primary unit of study in construction grammar theories. In construction grammar, cognitive grammar, and cognitive linguistics, a grammatical construction is a syntactic template that is paired with conventionalized semantic and pragmatic content. In generative frameworks, constructions are generally treated as epiphenomenal, being derived by the general syntactic rules of the language in question.