The Spivak pronouns are a set of gender-neutral pronouns in English promulgated on the virtual community LambdaMOO based on pronouns used in a book by American mathematician Michael Spivak. Though not in widespread use, they have been employed in writing for gender-neutral language by those who wish to avoid the standard terms "he/she" or singular they. Three variants of the Spivak pronouns are in use, Rogers (1890), Elverson (1975), and LambdaMOO (1991), highlighted in the declension table below.