
Of the Origin and Progress of Language (Edinburgh and London: J. Balfour and T. Cadell, 2nd ed., 1774), Vol. I, Book II, Ch. II, pp. 224-225 https://archive.org/stream/originandprogre01conggoog#page/n251/mode/2up.
Sylvester Graham's Lectures on the Science of Human Life https://books.google.it/books?id=nRwDAAAAQAAJ, condensed by T. Baker, Manchester: John Heywood, 1881, p. 76.
Of the Origin and Progress of Language (Edinburgh and London: J. Balfour and T. Cadell, 2nd ed., 1774), Vol. I, Book II, Ch. II, pp. 224-225 https://archive.org/stream/originandprogre01conggoog#page/n251/mode/2up.
Essays on Diet (1883); quoted in Prof. Francis William Newman http://www.ivu.org/history/europe19b/newman.html at the International Vegetarian Union website.
The Animal Kingdom https://books.google.it/books?id=gKBgAAAAcAAJ&pg=PA0, trans. H. McMurtrie, London: Orr and Smith, 1834, p. 37.
Source: Sayings of Sri Ramakrishna (1960), p. 867
The Anatomy, Physiology, and Diseases of the Teeth, Philadelphia: Carey & Lea, 1830, p. 35 https://books.google.it/books?id=LK-_LIeEq2oC&pg=PA35&lpg=PA35.
“Man, in his animal capacity, is qualified to subsist in every climate.”
PART III, SECTION I.
An Essay on the History of Civil Society (1767)
“Ideas,” Lucinde and the Fragments, P. Firchow, trans. (1991), § 5
Source: About Looking (1980), Chapter "Why Look at Animals?"
Source: A Plea for the Animals (2014), Chapter 6, p. 132