Non-rivalrous is an economic term that describes a situation where the consumption of a good or service by one person does not reduce the amount available for consumption by others. This is in contrast to rivalrous goods, which are typically finite in nature and where usage by one person necessarily makes it less available for other consumers. An example of a non-rivalrous good is knowledge, which can be used infinitely at no cost to others. In essence, non-rivalrous goods are almost infinitely divisible among the population with no one being worse off.

See also: emergence, evolutionary computing, proto b