This document discusses measuring and manipulating player trust through game mechanics and choices. It defines trust and reputation, noting that trust concerns moral hazard while reputation concerns adverse selection. It argues that trustworthiness is isomorphic to an agent's discount factor in game theory. Several ways are described to measure a player's discount factor through their choices in a game. The document also discusses using non-player characters with varying levels of trustworthiness to explore and exploit a player's trust. Finally, it outlines direct applications of these concepts like determining NPC decisions and subordinates' obedience based on the player's measured trustworthiness.