Then there are stipulative definitions, which are terms introduced and defined by fiat. A circle in Euclidean geometry can be defined as a round plane figure whose boundary consists of infinite points equidistant to a single other point. There are no possible counterexamples to this definition, given the axioms of Euclidean geometry. This approach provides little refuge in the real world. Consider an attempt to define swans as “white birds with long necks.” By stipulation, storks, great egrets, and many cranes would be swans, while Australia’s black swans would not. Such a quick and dirty definition seems to define the category out of hand and perhaps only works within accepted axioms or theories. Life could be stipulated as “carbon-based reproducing entities,” which would rule out silicon-based life by fiat. Such a definition merely pushes the debate to the scenarios in which the stipulated definition goes against intuitive notions.