The forms and terminology of propositional logic carry over into predicate logic - literals, logical expressions, clauses, terms, conjunctive normal form, disjunctive normal form, etc. A literal is either an atomic formula or its negation. If a literal has no variables it is a ground literal . 9AM CS101 Turing Aud. Ohm Hall CS101 F 9AM PH100 Newton Lab.
Every atomic formula is an expression.
Precedence of Operators Parentheses may still be used. In their absence we used the same precedence as propositional logic and include the quantifiers with highest precedence. Don't confuse the order of quantifiers. The X in the first quantifier is not related at all to the X in the second. If we look at the expression tree we see that the variable named in a quantifier only binds like named variables in the subtree rooted at the quantifier.