“It is a fact that humans are multicellular eukaryotes with an internal digestive tract. It is also a fact that these criteria match the biological definition of an animal. But because I’m talking to a philosopher, we even have to argue the definition of “definition”. “A good definition explains concisely what something means“, “a statement expressing the essential nature of something“, “a statement of what a thing is“. So any multicellular eukaryote with an internal digestive tract is in fact an animal by definition. Once we determine that the criteria apply, we have no choice to deny the definition connected with that, especially not when the definition is deliberately well-established by expertise as this one is, rather than being an “accident of language” such as the apologist asserted.”

Source: The Limits of Evolution, and Other Essays, Illustrating the Metaphysical Theory of Personal Ideaalism (1905), The Harmony of Determinism and Freedom, p.320

Part of the speech to the students of the Georgia Institute of Technology, On the subject of humane slaughter (Summer 2010)
Context: Exactly what is your definition of humane? Besides psychological and physical abuse, torture, dismemberment and murder, what else do you think happens to animals inside of a slaughterhouse? Do you think they get belly rubs and tushy slaps? And if you think there is such a thing as humane slaughter. I'm curious, do you also think there is such a thing as humane rape? Humane child molestation? Humane slavery? How about a humane holocaust? In fact, what is your definition of a holocaust? Is it a massacre of human beings, or a massacre of innocent beings?

Source: The Inefficient Stock Market - What Pays Off And Why (1999), Chapter 2, Estimating Expected Return with the Theories of Modern Finance, p. 16

Exclusive Interview with Aron Ra – Public Speaker, Atheist Vlogger, and Activist https://conatusnews.com/interview-aron-ra-past-president-atheist-alliance-america/, Conatus News (May 17, 2017)

Letter to William James (8 January 1909)

"How the Poor Die" http://orwell.ru/library/articles/Poor_Die/english/e_pdie, Now (November 1946)

Language Education in a Knowledge Context (1980)
Context: Definitions, like questions and metaphors, are instruments for thinking. Their authority rests entirely on their usefulness, not their correctness. We use definitions in order to delineate problems we wish to investigate, or to further interests we wish to promote. In other words, we invent definitions and discard them as suits our purposes. And yet, one gets the impression that... God has provided us with definitions from which we depart at the risk of losing our immortal souls. This is the belief that I have elsewhere called "definition tyranny," which may be defined... as the process of accepting without criticism someone else's definition of a word or a problem or a situation. I can think of no better method of freeing students from this obstruction of the mind than to provide them with alternative definitions of every concept and term with which they must deal in a subject. Whether it be "molecule," "fact," "law," "art," "wealth," "gene," or whatever, it is essential that students understand that definitions are hypotheses, and that embedded in them is a particular philosophical, sociological, or epistemological point of view.

Methods of Mathematics Applied to Calculus, Probability, and Statistics (1985)

Interview quoted in Timothy Steele 'Introduction & Commentary-Poetry of J V Cunningham'
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