Informal fallacies in the context of Argument

Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical truths. It examines how conclusions follow from premises based on the structure of arguments alone, independent of their topic and content. Informal logic is associated with informal fallacies, critical thinking, and argumentation theory. Informal logic examines arguments expressed in natural language whereas formal logic uses formal language. When used as a countable noun, the term "a logic" refers to a specific logical formal system that articulates a proof system. Logic plays a central role in many fields, such as philosophy, mathematics, computer science, and linguistics.

Logic studies arguments, which consist of a set of premises that leads to a conclusion. An example is the argument from the premises "it's Sunday" and "if it's Sunday then I don't have to work" leading to the conclusion "I don't have to work." Premises and conclusions express propositions or claims that can be true or false. An important feature of propositions is their internal structure. For example, complex propositions are made up of simpler propositions linked by logical vocabulary like ${\displaystyle \land }$ (and) or ${\displaystyle \to }$ (if...then). Simple propositions also have parts, like "Sunday" or "work" in the example. The truth of a proposition usually depends on the meanings of all of its parts. However, this is not the case for logically true propositions. They are true only because of their logical structure independent of the specific meanings of the individual parts.

Informal logic encompasses the principles of logic and logical thought outside of a formal setting (characterized by the usage of particular statements). However, the precise definition of "informal logic" is a matter of some dispute. Ralph H. Johnson and J. Anthony Blair define informal logic as "a branch of logic whose task is to develop non-formal standards, criteria, procedures for the analysis, interpretation, evaluation, criticism and construction of argumentation." This definition reflects what had been implicit in their practice and what others were doing in their informal logic texts.

Informal logic is associated with informal fallacies, critical thinking, the thinking skills movement and the interdisciplinary inquiry known as argumentation theory. Frans H. van Eemeren writes that the label "informal logic" covers a "collection of normative approaches to the study of reasoning in ordinary language that remain closer to the practice of argumentation than formal logic."

In literary theory and aesthetics, authorial intent refers to an author's intent as it is encoded in their work. Authorial intentionalism is the hermeneutical view that an author's intentions should constrain the ways in which a text is properly interpreted. Opponents, who dispute its hermeneutical importance, have labelled this position the intentional fallacy and count it among the informal fallacies.

There are in fact two types of Intentionalism: Actual Intentionalism and Hypothetical Intentionalism. Actual Intentionalism is the standard intentionalist view that the meaning of a work is dependent on authorial intent. Hypothetical Intentionalism is a more recent view; it views the meaning of a work as being what an ideal reader would hypothesize the writer's intent to have been — for hypothetical intentionalism, it is ultimately the hypothesis of the reader, not the truth, that matters.