Bundle theory is a way of thinking about what makes up a person. It says that a person isn't just one thing, like a body or a mind. Instead, a person is made up of lots of different things all bundled together in one. These things might include your thoughts, feelings, beliefs, memories, body, the way others see you — all the things that make you unique. All of these things could be seen as a bundle, like a package of things wrapped up together.