“When a truth is better conceived through abstraction, use the abstraction; if not, don't.”

Quote from Van Doesburg's article 'Elementarism as real art', in: 'Painting and plastic art' - Rome, July 1926, in De Stijl', series XIII, 1 75-6, 1926, pp. 35–43
1926 – 1931

The Grass Is Singing, ch. 2 (1950)

"The Designers and the Politicians" (1962), later published in Ideas and Integrities : A Spontaneous Autobiographical Disclosure (1969), p. 233, and The Buckminster Fuller Reader (1970), p. 305
1960s
Context: Relativity is inherently convergent, though convergent toward a plurality of centers of abstract truths. Degrees of accuracy are only degrees of refinement and magnitude in no way affects the fundamental reliability, which refers, as directional or angular sense, toward centralized truths. Truth is a relationship.

(2004), p. v
How Maps Work: Representation, Visualization, and Design (1995)

[O] : Introduction, 0.6
Semiotics and the Philosophy of Language (1984)
Context: When semiotics posits such concepts as 'sign', it does not act like a science; it acts like philosophy when it posits such abstractions as subject, good and evil, truth or revolution. Now, a philosophy is not a science, because its assertions cannot be empirically tested … Philosophical entities exist only insofar as they have been philosophically posited. Outside their philosophical framework, the empirical data that a philosophy organizes lose every possible unity and cohesion.
To walk, to make love, to sleep, to refrain from doing something, to give food to someone else, to eat roast beef on Friday — each is either a physical event or the absence of a physical event, or a relation between two or more physical events. However, each becomes an instance of good, bad, or neutral behavior within a given philosophical framework. Outside such a framework, to eat roast beef is radically different from making love, and making love is always the same sort of activity independent of the legal status of the partners. From a given philosophical point of view, both to eat roast beef on Friday and to make love to x can become instances of 'sin', whereas both to give food to someone and to make love to у can become instances of virtuous action.
Good or bad are theoretical stipulations according to which, by a philosophical decision, many scattered instances of the most different facts or acts become the same thing. It is interesting to remark that also the notions of 'object', 'phenomenon', or 'natural kind', as used by the natural sciences, share the same philosophical nature. This is certainly not the case of specific semiotics or of a human science such as cultural anthropology.

Source: Object-oriented design: With Applications, (1991), p. 54

Source: Barsk: The Elephants' Graveyard (2015), Chapter 7, “Parental Disappointment” (p. 84)

12 October 1859 (p. 388)
1831 - 1863, Delacroix' 'Journal' (1847 – 1863)