Monday, August 31, 2009

What is meant by a priori and a posteriori

The terms used to describe the logical status of propositions and arguments with respect to their dependence upon, or independence from, sense experiences. An a priori proposition is one that can be determined to be true independently of sense experience. The statement "all bachelors are unmarried men" is a statement that is independent of empirical testing. A bachelor by definition is an unmarried man.

An a posteriori proposition is one that known on the basis of sense experience.