Found:

Propositional logic

**SEMANTICS: **the logical system which takes sentences and their
combinations as primitives. The **logical constant**s of the language are negation and the connectives &, v, ->, and <->.
**Propositional letters** (also atomic propositions) are combined with these connectives into more complex
**propositional formula**s according to the syntax of propositional logic. The semantics interprets the meaning of the logical constants in terms of truth-values. Propositional logic characterizes a particular class of valid arguments, like the one in (i).

(i) If the sun is shining, then John is happy The sun is shining Therefore, John is happyWhen we translate the natural language statements in (i) into propositional logic (as in (ii)) we get the schema in (iii).

(ii) p: the sun is shining q: John is happy (iii) p -> q p ------ qTranslation into propositional logic makes it clear that the argument in (i) is valid because of certain logical constants. The validity of the schema in (iii) can be demonstrated with a formal syntactic deduction or by means of a truth-table.

LIT. | Gamut, L.T.F. (1991) |