Non-monotonic reasoning is a type of logical reasoning where the introduction of new information can change previous conclusions. Unlike traditional logic, where once something is proven true it remains true, non-monotonic reasoning allows for flexibility and adaptation as new evidence emerges. This is particularly useful in real-world situations where information is often incomplete or evolving. An example of non-monotonic reasoning can be seen in everyday decision-making. For instance, if you believe that birds can fly, but then learn that ostriches cannot, your conclusion about birds must be adjusted. This adaptability makes non-monotonic reasoning essential in fields like artificial intelligence and law, where circumstances frequently change.