An antecedent is the first half of a hypothetical proposition, whenever the if-clause precedes the then-clause. It is also known for a person's principles to a possible or hypothetical issue. In some contexts the antecedent is called the protasis.
- If P, then Q.
This is a nonlogical formulation of a hypothetical proposition. In this case, the antecedent is P, and the consequent is Q. In an implication, if implies then is called the antecedent and is called the consequent.
- If X is a man, then X is mortal.
"X is a man" is the antecedent for this proposition.
- If men have walked on the moon, then I am the king of France.
Here, "men have walked on the moon" is the antecedent.
- See Conditional sentence.
- Sets, Functions and Logic - An Introduction to Abstract Mathematics, Keith Devlin, Chapman & Hall/CRC Mathematics, 3rd ed., 2004