Nonsense in the context of "Theological noncognitivism"

Cryptography, or cryptology (from Ancient Greek: κρυπτός, romanized: kryptós "hidden, secret"; and γράφειν graphein, "to write", or -λογία -logia, "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security (data confidentiality, data integrity, authentication and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords and military communications.

Cryptography prior to the modern age was effectively synonymous with encryption, converting readable information (plaintext) to unintelligible nonsense text (ciphertext), which can only be read by reversing the process (decryption). The sender of an encrypted (coded) message shares the decryption (decoding) technique only with the intended recipients to preclude access from adversaries. The cryptography literature often uses the names "Alice" (or "A") for the sender, "Bob" (or "B") for the intended recipient, and "Eve" (or "E") for the eavesdropping adversary. Since the development of rotor cipher machines in World War I and the advent of computers in World War II, cryptography methods have become increasingly complex and their applications more varied.

Colorless green ideas sleep furiously was composed by Noam Chomsky in his 1957 book Syntactic Structures as an example of a sentence that is grammatically well-formed, but semantically nonsensical. The sentence was originally used in his 1955 thesis The Logical Structure of Linguistic Theory and in his 1956 paper "Three Models for the Description of Language". There is no obvious understandable meaning that can be derived from it, which demonstrates the distinction between syntax and semantics, and the idea that a syntactically well-formed sentence is not guaranteed to also be semantically well-formed. As an example of a category mistake, it was intended to show the inadequacy of certain probabilistic models of grammar, and the need for more structured models.

In logic, syntax is an arrangement of well-structured entities in the formal languages or formal systems that express something. Syntax is concerned with the rules used for constructing or transforming the symbols and words of a language, as contrasted with the semantics of a language, which is concerned with its meaning.

The symbols, formulas, systems, theorems and proofs expressed in formal languages are syntactic entities whose properties may be studied without regard to any meaning they may be given, and, in fact, need not be given any.

A logical symbol is a fundamental concept in logic, tokens of which may be marks or a configuration of marks which form a particular pattern. Although the term symbol in common use sometimes refers to the idea being symbolized, and at other times to the marks on a piece of paper or chalkboard which are being used to express that idea; in the formal languages studied in mathematics and logic, the term symbol refers to the idea, and the marks are considered to be a token instance of the symbol. In logic, symbols build literal utility to illustrate ideas.

Absurdity is the state or condition of being unreasonable, meaningless, or so unsound as to be irrational. "Absurd" is the adjective used to describe absurdity, e.g., "Tyler and the boys laughed at the absurd situation." It derives from the Latin absurdum meaning "out of tune". The Latin surdus means "deaf", implying stupidity.Absurdity is contrasted with being realistic or reasonable. In general usage, absurdity may be synonymous with nonsense, meaninglessness, fancifulness, foolishness, bizarreness, wildness. In specialized usage, absurdity is related to extremes in bad reasoning or pointlessness in reasoning; ridiculousness is related to extremes of incongruous juxtaposition, laughter, and ridicule; and nonsense is related to a lack of meaningfulness. Absurdism is a concept in philosophy related to the notion of absurdity.

Surreal humour (also called surreal comedy, absurdist humour, or absurdist comedy) is a form of humour predicated on deliberate violations of causal reasoning, thus producing events and behaviours that are obviously illogical. Portrayals of surreal humour tend to involve bizarre juxtapositions, incongruity, non-sequiturs, irrational or absurd situations, and expressions of nonsense.

Surreal humour grew out of surrealism, a cultural movement developed in the 20th century by French and Belgian artists, who depicted unnerving and illogical scenes while developing techniques to allow the unconscious mind to express itself. The movement itself was foreshadowed by English writers in the 19th century, most notably Lewis Carroll and Edward Lear. The humour in surreal comedy arises from a subversion of audience expectations, emphasising the ridiculousness and unlikeliness of a situation, so that amusement is founded on an unpredictability that is separate from a logical analysis of the situation.

To be ridiculous is to be something highly incongruous or inferior, sometimes deliberately so to make people laugh or get their attention, and sometimes unintendedly so as to be considered laughable and earn or provoke ridicule and derision. It comes from the 1540s Latin "ridiculosus" meaning "laughable", from "ridiculus" meaning "that which excites laughter", and from "ridere" meaning "to laugh". "Ridiculous" is an adjective describing "the ridiculous".

In common usage, "ridiculousness" is used as a synonym for absurdity or nonsense. From a historical and technical viewpoint, "absurdity" is associated with argumentation and reasoning, "nonsense" with semantics and meaning, while "ridiculous" is most associated with laughter, superiority, deformity, and incongruity. Reductio ad absurdum is a valid method of argument, while reductio ad ridiculum is invalid. Argument by invective declaration of ridiculous is invalid, while arguments involving declarations of nonsense may summarize a cogent semantic problem with lack or meaning or ambiguity.