Jan Tschichold quote: “The works of 'abstract' art are subtle creations of order out of simple contrasting elements.”

“The chief element of creation is love and the chief action of love is Art.”

Laxmi Prasad Devkota (1909–1959) Nepali poet

कला र जीवन (Art and Life)
Art and Life

“The conflict between the theories of Surrealism & pure abstraction leads many to look upon one as black & bad & the other as white & good. Yet it seems to me that a good work of art has always contained both abstract & surrealist elements – just as it has both classical & romantic elements (order & surprise?)... Surrealism is widening the field of contemporary art & is giving more freedom to the artist (& perhaps what is not unimportant, – stretching the appreciation of the public). Abstraction is re-establishing fundamental laws; bringing back form to painting & sculpture. There are many products of surrealism which I personally dislike,.... but equally Unimportant to me are the empty decorations produced in the name of abstraction.”

Henry Moore (1898–1986) English artist

Source: 1925 - 1940, Unpublished notes' for 'The Sculptor Speaks' (1937), pp. 112-113

“Yes, there was an element of abstraction and unreality in misfortune. But when an abstraction starts to kill you, you have to get to work on it.”

Albert Camus book The Plague

The Plague (1947)

“Feeling must have a medium in order to function at all; in the same way, thought must have symbols. It is the medium, or the specific configuration of the medium that we call a work of art that brings feeling into being, just as do responses tot the objects of the external world... The medium of painting is such changing and ordering on an ideal plane, ideal in that the medium is more tractable, subtle, and capable of emphasis (abstraction is a kind of emphasis) than everyday life.”

Mark Rothko (1903–1970) American painter

Source: 1940's, Beyond the Aesthetics (1946), pp. 38-39

“Feeling must have a medium in order to function at all; in the same way, thought must have symbols. It is the medium, or the specific configuration of the medium that we call a work of art that brings feeling into being, just as do responses tot the objects of the external world... The medium of painting is such changing and ordering on an ideal plane, ideal in that the medium is more tractable, subtle, and capable of emphasis (abstraction is a kind of emphasis) than everyday life.”

Robert Motherwell (1915–1991) American artist

Source: 1940s, Beyond the Aesthetics' (1946), pp. 38-39

“Our bodies are shaped to bear children, and our lives are a working out of the processes of creation. All our ambitions and intelligence are beside that great elemental point.”

Aurelius Augustinus (354–430) early Christian theologian and philosopher

Sometimes attributed to Augustine, but is from Phyllis McGinley https://en.wikipedia.org/wiki/Phyllis_McGinley, The Province of the Heart, "The Honor of Being a Woman" (1959).
Misattributed

“As for a few others, the vital task was a wedding of abstraction and surrealism. Out of these opposites something new could emerge, and Gorky’s work is a part of the evidence that this is true. What he felt, I suppose, was a sense of polarity, not of dichotomy; that opposites could exist simultaneously within a body, within a painting or within an entire art... These are the opposites poles in his work. Logic and irrationality; violence and gentleness; happiness and sadness, surrealism and abstraction. Out of these elements I think Gorky evolved his style.”

Adolph Gottlieb (1903–1974) American artist

Arshile Gorky Adolph Gottlieb in exhibition catalogue Kootz Gallery New York, 1950; as quoted in Abstract Painting in America, W.C, Seitz p. 104.
1950s