This document discusses mitigating circumstances under Article 13 of the Revised Penal Code of the Philippines. It defines mitigating circumstances as factors that lessen criminal liability and reduce the penalty for a crime. There are ordinary mitigating circumstances explicitly listed in the code as well as privileged mitigating circumstances like minority. The document examines several specific ordinary mitigating circumstances in detail, such as insufficient provocation, immediate vindication of a grave offense, and voluntary surrender. It also distinguishes ordinary from privileged mitigating circumstances in terms of how they affect penalties.