How do you call a person who knows everything?

Answer 1

A person who knows everything is often referred to as a "polymath" or "omniscient." However, the term "know-it-all" is commonly used in a more informal or colloquial context, often with a negative connotation, to describe someone who believes they have knowledge on every subject. In a more philosophical sense, the concept of omniscience pertains to knowing all truths, which is typically attributed to a deity rather than a human.