The document discusses the representativeness heuristic, which is a mental shortcut used in decision making where people judge the probability of something based on how much it resembles or represents a prototype. It can lead to biases by overlooking important details and making incorrect judgments based on stereotypes. However, it also allows for quick decision making and identifying patterns. The document recommends seeking diverse perspectives, using data, and taking time to reflect to mitigate the effects of this heuristic.