This document summarizes what is known and not known about finance based on Chapter 25 of the textbook "Fundamentals of Corporate Finance". It lists the key concepts that are well established in finance theory, such as net present value, risk and return, efficient capital markets, and option theory. It also outlines important questions that remain unknown, such as what fully determines project risk and present value, whether the understanding of risk and return is incomplete, and how to explain observed phenomena like capital structure choices, merger waves, and the value of liquidity.