“One of my problems is to find the Ego, which has only one form and is immortal – to find it in animals and men, in the heaven and in the hell which together form the world in which we live.”
1930s, On my Painting (1938)
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Max Beckmann 52
German painter, draftsman, printmaker, sculptor and writer 1884–1950Related quotes

and thus is one of the previous two types of problem
Source: Solving Mathematical Problems (2nd ed., 2006), Ch. 1 : Strategies in problem solving

As quoted in Modern Dancing and Dancers (1912) by John Ernest Crawford Flitch, p. 105.
Context: To seek in nature the fairest forms and to find the movement which expresses the soul of these forms — this is the art of the dancer. It is from nature alone that the dancer must draw his inspirations, in the same manner as the sculptor, with whom he has so many affinities. Rodin has said: "To produce good sculpture it is not necessary to copy the works of antiquity; it is necessary first of all to regard the works of nature, and to see in those of the classics only the method by which they have interpreted nature." Rodin is right; and in my art I have by no means copied, as has been supposed, the figures of Greek vases, friezes and paintings. From them I have learned to regard nature, and when certain of my movements recall the gestures that are seen in works of art, it is only because, like them, they are drawn from the grand natural source.
My inspiration has been drawn from trees, from waves, from clouds, from the sympathies that exist between passion and the storm, between gentleness and the soft breeze, and the like, and I always endeavour to put into my movements a little of that divine continuity which gives to the whole of nature its beauty and its life.

Source: The Limits of State Action (1792), Ch. 16

...there is such a thing as the square root of 6, and it is denoted by √<span style="text-decoration: overline">6</span>. But we do not say we actually find this, but that we approximate to it.
The Differential and Integral Calculus (1836)

Charge to the Grand Jury of Ulster County http://www.johnjayinstitute.org/resources/publications/john-jays-charge-to-the-grand-jury-of-ulster-county-1777-and-charge-to-the/ (1777).
1770s

Introductory notes for Diatope performance, 1978 http://www.moderecords.com/catalog/148xenakis.html