from the beginning
"At the outset", referring to an inquiry or investigation. In literature, refers to a story told from the beginning rather than in medias res (from the middle). In law, refers to something being the case from the start or from the instant of the act, rather than from when the court declared it so. A judicial declaration of the invalidity of a marriage ab initio is a nullity. In science, refers to the first principles. In other contexts, often refers to beginner or training courses. Ab initio mundi means "from the beginning of the world".