“Every animal is sad after coitus except the human female and the rooster.”
Galen (30-200 A.D.), in: Medical Aspects of Human Sexuality, (1973), p. 19.
Latter day attributions
Original
Triste est omne animale post coitum, praeter mulierem gallumque
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Galén 11
Roman physician, surgeon and philosopher 129–216Related quotes

“There is a reward for kindness to every living animal or human.”
Muhammad narrated in Saheeh Muslim, #2244, and Saheeh Al-Bukhari, #2466.
Sunni Hadith

Pacquiao's stand on Same-Sex marriage
As quoted in Manny Pacquiao’s stand on same-sex marriage: ‘Mas masahol pa sa hayop ang tao’ http://www.interaksyon.com/interaktv/manny-pacquiaos-stand-on-same-sex-marriage-mas-masahol-pa-sa-hayop-ang-tao InterAksyon, February 15, 2016
Letter to David C.C. Watson, 23 April 1984. Quoted from https://answersingenesis.org/ https://answersingenesis.org/genesis/oxford-hebrew-scholar-professor-james-barr-meaning-of-genesis/
link https://web.archive.org/web/20170612180930/http://members.iinet.com.au:80/~sejones/barrlett.html Source: The authenticity of this letter is not verified yet.

“We do survive every moment, after all, except the last one.”

“Dawn will come even if the rooster is strangled.”
As quoted in "Kim Young-sam: Former President of South Korea Dies at 87" http://www.nytimes.com/2015/11/22/world/asia/kim-young-sam-former-president-of-south-korea-dies-at-87.html?_r=0 (November 2015), by Sang-Hun Choe, The New York Times (22 November 2015), New York

Karmas and Diseases, Divine Life Society, http://dlshq.org/download/karmadisease.htm (1959)

“Accident ruled every corner of the universe except the chambers of the human heart.”
Source: Snow Falling on Cedars (1994), Ch. 32, last page.