A priori

• A priori - pronounced 'eh-preye-OR-eye' (IPA: /eɪ prɜɪ 'ɔːrɜɪ/) or, keeping closer to the original Pronunciation of Classical Latin, 'ah pri-OR-i' (IPA: /ɑː prɪ 'ɔːrɪ/) - means literally 'from what comes before'.

• In philosophy an a priori statement is a statement that can be known to be true (or false) before, or independently of, any experience of the world. Such a statement, if true, can be said to be an a priori truth, and, if false, to be an a priori falsehood. We can also say that such statements can be known (to be true or false) a priori.

The opposite of 'a priori' is 'a posteriori' - pronounced 'eh-pos-ter-i-OR-eye' (IPA: /eɪ pɒs tɛr ɪ 'ɔːrɜɪ/) or 'ah pos-ter-i-OR-i' (IPA: /ɑː pɒs tɛr ɪ 'ɔːr ɪ/). It means literally 'from what comes after'.

For more information about the pronunciation of this and some other Latin expressions see Pronunciation of 'Lawyers' Latin' and Pronunciation of Classical Latin.