“Entities should not be multiplied beyond necessity.”
Though widely cited as Occam's razor, this popular wording is not found in his extant works.
Misattributed
Original
Entia non sunt multiplicanda praeter necessitatem.
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William of Ockham 13
medieval philosopher and theologian 1285–1349Related quotes

Systematic Theology (1951–63)
Context: Man is infinitely concerned about the infinity to which he belongs, from which he is separated, and for which he is longing. Man is totally concerned about the totality which is his true being and which is disrupted in time and space. Man is unconditionally concerned about that which conditions his being beyond all the conditions in him and around him. Man is ultimately concerned about that which determines his ultimate destiny beyond all preliminary necessities and accidents.

Nam June Paik (1965), as cited in: David Dunn, " A History of Electronic Music Pioneers http://vasulka.org/Kitchen/PDF_Eigenwelt/pdf/021-062.pdf." ders.(Hrsg.), Eigenwelt der Apparate-Welt.(Katalog), Linz (1992): 21-62.
1960s

Karl Popper, The Open Society and its Enemies, Vol I Plato Chapter 5: Nature and Convention. P. 67
The Open Society and Its Enemies (1945)
Context: In speaking of sociological laws or natural laws of social life I have in mind such laws as are formulated by modern economic theories, for instance, the theory of international trade, or the theory of the trade cycle. These and other important sociological laws are connected with the functioning of social institutions. These laws play a role in our social life corresponding to the role played in mechanical engineering by, say, the principle of the lever. For institutions, like levers, are needed if we want to achieve anything which goes beyond the power of our muscles. Like machines, institutions multiply our power for good or evil. Like machines, they need intelligent supervision by someone who understands their way of functioning and, most of all, their purpose, since we cannot build them so that they work entirely automatically.

11
Auxiliaries to the Perception of Intelligible Natures

For My Legionaries: The Iron Guard (1936), Politics
Travis McGee series, A Purple Place for Dying (1964)
Context: ... it is like what we have done to chickens. Forced growth under optimum conditions, so that in eight weeks they are ready for the mechanical picker. The most forlorn and comical statements are the ones made by the grateful young who say Now I can be ready in two years and nine months to go out in and earn a living rather than wasting 4 years in college. Education is something that should be apart from the necessities of earning a living, not a tool therefore. It needs contemplation, fallow periods, the measured and guided study of the history of man’s reiteration of the most agonizing question of all: Why? Today the good ones, the ones who want to ask why, find no one around with any interest in answering the question, so they drop out, because theirs is the type of mind which becomes monstrously bored at the trade-school concept. A devoted technician is seldom an educated man. He can be a useful man, a contented man, a busy man. But he has no more sense of the mystery and wonder and paradox of existence than does one of those chickens fattening itself for the mechanical plucking, freezing and packaging.