"Natalia Villaveces' Exclusive PETA Interview", video on PETA's YouTube channel (12 July 2011) https://www.youtube.com/watch?v=SX2alBCT70s.
“In fact if one person is unkind to an animal it is considered to be cruelty, but where a lot of people are unkind to a lot of animals, especially in the name of commerce, the cruelty is condoned and, once large sums of money are at stake, will be defended to the last by otherwise intelligent people.”
Animal Machines (1964; rev. ed. Boston: CABI, 2013), ch. IX, p. 175 https://books.google.it/books?id=7_3-ko8zyZYC&pg=PA175.
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Ruth Harrison 1
British activist 1920–2000Related quotes

“As long as man eats animals how can cruelty to animals be removed.”
19th World Vegetarian Congress 1967

“Be kind to unkind people. They need it the most.”
“Lots of people talk to animals… Not very many listen though… that's the problem.”
Source: The Tao of Pooh

Veg Family, March, 2003 http://www.vegfamily.com/interviews/ingrid-newkirk.htm

“More power to [Stop Huntingdon Animal Cruelty] if they can get someone’s attention.”
The Boston Herald, 2002 August 25.
2002

"Don’t Cover Up Animal Cruelty" https://www.huffingtonpost.com/cloris-leachman/post_1981_b_854721.html, in the HuffPost (27 April 2011).