“My volition shrinks from the painful task of recalling my humiliation; yet, like a second Prometheus, I will endure this and worse, if by any means I may arouse in the interiors of Plane and Solid Humanity a spirit of rebellion against the Conceit which would limit our Dimensions to Two or Three or any number short of Infinity.”

Translation source: Yuzuru Hanyu – World Championships 2021 ‘Day After’ Interview https://axelwithwings.com/2021/03/30/eng-translation-yuzuru-hanyu-world-championships-2021-day-after-interview-210328/ by Axel with Wings, published 28 March 2021. (Retrieved 31 March 2021)
Other quotes, 2021
Original: (ja) なんか限界だなって感じはないです。ただ、この限界だなって思うかもしれない時期をどうやって乗り越えていくか。
Source: Part 1 of the final interview at Worlds 2021 in Stockholm, as quoted in an article https://www.sponichi.co.jp/sports/news/2021/03/28/kiji/20210328s00079000616000c.html by Nippon Sports (Sponichi), published 28 March 2021. (Retrieved 31 March 2021)

Nor can our Fansie imagine how there should be a Fourth Local Dimension beyond these Three.
Treatise of Algebra (1685)

Source: Flatland: A Romance of Many Dimensions (1884), PART II: OTHER WORLDS, Chapter 22. How I Then Tried to Diffuse the Theory of Three Dimensions by Other Means, and of the Result
Context: My brother is one of the best of Squares, just, sensible, cheerful, and not without fraternal affection; yet I confess that my weekly interviews, at least in one respect, cause me the bitterest pain. He was present when the Sphere manifested himself in the Council Chamber; he saw the Sphere's changing sections; he heard the explanation of the phenomena then given to the Circles. Since that time, scarcely a week has passed during seven whole years, without his hearing from me a repetition of the part I played in that manifestation, together with ample descriptions of all the phenomena in Spaceland, and the arguments for the existence of Solid things derivable from Analogy. Yet — I take shame to be forced to confess it — my brother has not yet grasped the nature of the Third Dimension, and frankly avows his disbelief in the existence of a Sphere.Hence I am absolutely destitute of converts, and, for aught that I can see, the millennial Revelation has been made to me for nothing. Prometheus up in Spaceland was bound for bringing down fire for mortals, but I — poor Flatland Prometheus — lie here in prison for bringing down nothing to my countrymen. Yet I exist in the hope that these memoirs, in some manner, I know not how, may find their way to the minds of humanity in Some Dimension, and may stir up a race of rebels who shall refuse to be confined to limited Dimensionality.That is the hope of my brighter moments. Alas, it is not always so. Heavily weighs on me at times the burdensome reflection that I cannot honestly say I am confident as to the exact shape of the once-seen, oft-regretted Cube; and in my nightly visions the mysterious precept, "Upward, not Northward", haunts me like a soul-devouring Sphinx. It is part of the martyrdom which I endure for the cause of the Truth that there are seasons of mental weakness, when Cubes and Spheres flit away into the background of scarce-possible existences; when the Land of Three Dimensions seems almost as visionary as the Land of One or None; nay, when even this hard wall that bars me from my freedom, these very tablets on which I am writing, and all the substantial realities of Flatland itself, appear no better than the offspring of a diseased imagination, or the baseless fabric of a dream.

Source: Nationalism and Culture (1937), Ch. 1 "The Insufficiency of Economic Materialism"
Context: Every process which arises from our physical being and is related to it, is an event which lies outside of our volition. Every social process, however, arises from human intentions and human goal setting and occurs within the limits of our volition. Consequently, it is not subject to the concept of natural necessity. … We are here stating no prejudiced opinion, but merely an established fact. Every result of human purposiveness is of indisputable importance for man's social existence, but we should stop regarding social processes as deterministic manifestations of a necessary course of events. Such a view can only lead to the most erroneous conclusions and contribute to a fatal confusion in our understanding of historical events.
It is doubtless the task of the historian to trace the inner connection of historical events and to make clear their causes and effects, but he must not forget that these connections are of a sort quite different from those of natural physical events and must therefore have quite a different valuation.

Source: Flatland: A Romance of Many Dimensions (1884), PART II: OTHER WORLDS, Chapter 19. How, Though the Sphere Showed Me Other Mysteries of Spaceland, I Still Desired More; and What Came of It
Context: I despair not that, even here, in this region of Three Dimensions, your Lordship's art may make the Fourth Dimension visible to me; just as in the Land of Two Dimensions my Teacher's skill would fain have opened the eyes of his blind servant to the invisible presence of a Third Dimension, though I saw it not.Let me recall the past. Was I not taught below that when I saw a Line and inferred a Plane, I in reality saw a Third unrecognized Dimension, not the same as brightness, called "height"? And does it not now follow that, in this region, when I see a Plane and infer a Solid, I really see a Fourth unrecognized Dimension, not the same as colour, but existent, though infinitesimal and incapable of measurement?

Source: A Tale for the Time Being

These opinions, I know, are quite sufficient to have me looked down upon as a mind of the fourth order.
Ecuador (1929)

Source: 1930s, On my Painting (1938), p. 16

Abstract
On the Space-Theory of Matter (read Feb 21, 1870)