Proposed alternatives to the generic "he" include "he or she" (or "she or he"), "s/he", or the use of singular "they". Each of these alternatives has met with objections. Some feel the use of singular "they" to be a grammatical error, but according to most references, "they", "their" and "them" have long been grammatically acceptable as gender-neutral singular pronouns in English, having been used in the singular continuously since the Middle Ages, including by a number of prominent authors, such as Geoffrey Chaucer, William Shakespeare, and Jane Austen. Linguist Steven Pinker goes further and argues that traditional grammar proscriptions regarding the use of singular "they" are themselves incorrect: