The economist Daniel McFadden has analyzed people's decision-making process in depth. In his research, every choice of people can be seen as a choice among a limited number of possibilities. Everyone has a utility function. The purpose is to use the maximum utility. For example, whether to go to work walking, cycling or riding is an optimization problem involving multiple characteristics. It includes the characteristics: actual expenditure, travel time, waiting time, comfort, etc. People can according to themselves We compare the different features to determine the best way. What does this text mean? ['The principle of maximum utility affects every decision people make.', 'The best way to solve a problem is often determined by personal preference.', "People's decision-making process is not only linear but also multi-dimensional.", 'Different people make different decisions under the same conditions.']