“The concept of space is not abstracted from external sensations.”

Source: posthumous quotes, Braque', (1968), p. 55

Source: Fallen Leaves (2014), Ch. 6 : Our Souls

"On the Physiological Causes of Harmony" (1857), p. 81
Popular Lectures on Scientific Subjects (1881)
Context: As you are aware, no perceptions obtained by the senses are merely sensations impressed on our nervous systems. A peculiar intellectual activity is required to pass from a nervous sensation to the conception of an external object, which the sensation has aroused. The sensations of our nerves of sense are mere symbols indicating certain external objects, and it is usually only after considerable practice that we acquire the power of drawing correct conclusions from our sensations respecting the corresponding objects.

Living Systems: Basic Concepts (1969)

VIII, 50
Meditations (c. 121–180 AD), Book VIII
Context: The universal nature has no external space; but the wondrous part of her art is that though she has circumscribed herself, everything which is within her which appears to decay and to grow old and to be useless she changes into herself, and again makes other new things from these very same, so that she requires neither substance from without nor wants a place into which she may cast that which decays. She is content then with her own space, and her own matter, and her own art.

Kant's Inaugural Dissertation (1770), Section II On The Distinction Between The Sensible And The Intelligible Generally

Source: Research challenges in geovisualization (2001), p. 6-7

Georg Wilhelm Friedrich Hegel, Philosophy of Right translated by SW Dyde Queen’s University Canada 1896 p. 123
Elements of the Philosophy of Right (1820/1821)
Context: The good is the idea, or unity of the conception of the will with the particular will. Abstract right, well-being, the subjectivity of consciousness, and the contingency of external reality, are in their independent and separate existences superseded in this unity, although in their real essence they are contained in it and preserved. This unity is realized freedom, the absolute final cause of the world. Addition.—Every stage is properly the idea, but the earlier steps contain the idea only in more abstract form. The I, as person, is already the idea, although in its most abstract guise. The good is the idea more completely determined; it is the unity of the conception of will with the particular will. It is not something abstractly right, but has a real content, whose substance constitutes both right and well-being.

Source: Ancillary Justice (2013), Chapter 4 (p. 54)