The spivak pronouns were developed by mathematician Michael Spivak for use in
 his books.  They are the most simplistic of the gender neutral pronouns
 (others being "neuter" and "splat") and can be easily integrated into
 writing.  They should be used in a generic setting where the gender of the
 person referred to is unknown, such as "the reader."  They can also be used
 to describe a specific individual who has chosen not to identify emself with
 the traditional masculine (male) or feminine (female) gender.

The spivak pronouns are
E      - subjective
Em     - objective
Eir    - possessive (adjective)
Eirs   - possessive (noun)
Emself - reflexive