Basic Concepts of Logic: Terms, Propositions and Arguments
Terms
A term is a word or group of words that can serve as subject or predicate of a proposition. Terms have denotation (the objects referred to) and connotation (the attributes implied). Terms may be singular, general or collective; a general term used collectively (“the team won”) differs from its distributive use (“each player won”).
Propositions and arguments
A proposition is a statement that is either true or false - unlike questions, commands, exclamations and wishes. Different sentences (“It is raining”, “Paus padtoy”) may express the same proposition. An argument is a set of propositions in which some (premises) are offered as support for another (conclusion). Indicator words matter: since, because, for, given that signal premises; therefore, hence, so, consequently signal conclusions.
Worked example
“Since all students who attend regularly pass, and Meera attends regularly, she will pass.” Since marks the first clause as a premise; and joins a second premise; the last clause is the conclusion. In standard form:
- All regular attenders pass.
- Meera is a regular attender. ∴ Meera passes.
Traps that cost marks
A single conditional sentence (“If it rains, the ground gets wet”) is not an argument - it asserts a relation, it does not infer. Do not treat every sentence containing “because” as an argument; sometimes it is one complex proposition. Do not confuse the number of sentences with the number of propositions.