The term heresy is from Greek αἵρεσις originally meant "choice" or "thing chosen", but it came to mean the "party or school of a man's choice" and also referred to that process whereby a young person would examine various philosophies to determine how to live. The word "heresy" is usually used within a Christian, Jewish, or Islamic context, and implies slightly different meanings in each. The founder or leader of a heretical movement is called a heresiarch, while individuals who espouse heresy or commit heresy are known as heretics. Heresiology is the study of heresy.