Quotes about subset
A collection of quotes on the topic of subset, system, use, idea.
Quotes about subset

Concepts

Lotfi Asker Zadeh, George Jiri Klir, Bo Yuan (1996) Fuzzy Sets, Fuzzy Logic, and Fuzzy Systems: Selected Papers. p. 238
1990s

The Cosmos as a Poem (2010)
Tideman and Tullock 1976
James Buchanan, Gordon Tullock, and The Calculus (2012)

Patheos, The Cow http://www.patheos.com/blogs/reasonadvocates/2016/01/22/the-cow/ (January 22, 2016)
Mellor and Ian Wilkie (1999). A mapping from Shlaer-Mellor to UML http://www.ooatool.com/docs/SMUML99.pdf. Technical report, Projtech Inc. and Kennedy Carter Limited, 1999.

Ken Thompson; cited in
"Coders At Work", 2009

“Poetry is a subset of a Cosmos, which in itself, is a poem.”
The Cosmos as a Poem (2010)

Opening sentence, p. 1
Sexual Personae: Art and Decadence from Nefertiti to Emily Dickinson (1990)

1990s, I Am a Man, a Black Man, an American (1998)

“Everything poetic exists as a subset of a whole, and within the authoritative system of Nature.”
The Cosmos as a Poem (2010)
making parents and teachers a subtype of animal trainers
Source: Darwin, God and the Meaning of Life: How Evolutionary Theory Undermines Everything You Think You Know (2010), p. 155

Wanderlust: A History of Walking (2001)

Software Engineering Radio Episode 140: Newspeak and Pluggable Types with Gilad Bracha http://www.se-radio.net/2009/07/episode-140-newspeak-and-pluggable-types-with-gilad-bracha/
Peace Science Society (International) (1975) Papers - Volumes 24-29. p. 53 summarized: "Boulding begins by explaining what he believes are the four basic concepts to describe a conflict in an analytical way : (1) the party; (2) the behavior space; (3) competition; (4) conflict."
Source: 1960s, Conflict and defense: A general theory, 1962, p. 3
Source: Living Systems: Basic Concepts (1969), p. 51; Opening paragraph
Source: Living systems, 1978, p. 41

Lotfi Asker Zadeh, George Klir, Bo Yuan (1996) Fuzzy Sets, Fuzzy Logic, and Fuzzy Systems: Selected Papers. p. 238.

Why our future depends on libraries, reading and daydreaming (2013)

Von Foerster (1963, p. ii) as cited in Peter M. Asaro (2007). "Heinz von Foerster and the Bio-Computing Movements of the 1960s," http://cybersophe.org/writing/Asaro%20HVF%26BCL.pdf
1960s
“I regard physics as that subset of magic that works fairly reliably.”
Source: The Apophenion (2008), p. 7
Context: I regard physics as that subset of magic that works fairly reliably. I regard magick, in the traditional sense, as a kind of physics that we strive to understand and render more reliable. So it all comes down to the same thing, a quest to understand and manipulate the world with a self-consistent and coherent theory.

Congresswoman Sheila Jackson Lee Statement on the Historic Hearing on H.R. 40 - a Bill to Establish a Commission to Study and Develop Reparation Proposals for African Americans (19 June 2019)
"The Hospitals Are Coming", in Narrow Roads of Gene Land, Volume 2: Evolution of Sex (2002)