“The sequence of different positions of the same particle at different times forms a one-dimensional continuum in the four-dimensional space-time, which is called the world-line of the particle. All that physical experiments or observations can teach us refers to intersections of world-lines of different material particles, light-pulsations, etc., and how the course of the world-line is between these points of intersection is entirely irrelevant and outside the domain of physics. The system of intersecting world-lines can thus be twisted about at will, so long as no points of intersection are destroyed or created, and their order is not changed. It follows that the equations expressing the physical laws must be invariant for arbitrary transformations.”
Kosmos (1932), Above is Beginning Quote of the Last Chapter: Relativity and Modern Theories of the Universe -->
Help us to complete the source, original and additional information
Willem de Sitter 44
Dutch cosmologist 1872–1934Related quotes

Source: Adventures In Consciousness: An Introduction to Aspect Psychology (1975), pp.118-119

The Epistle to the Romans (1918; 1921)
Context: The known plane is God's creation, fallen out of its union with Him, and therefore the world of the flesh needing redemption, the world of men, and of time, and of things — our world. This known plane is intersected by another plane that is unknown — the world of the Father, of the Primal Creation, and of the final Redemption. The relation between us and God, between this world and His world presses for recognition, but the line of intersection is not self-evident. <!-- p. 29

and it goes from there.
Vanna Bonta Talks About Quantum fiction: Author Interview (2007)

Kosmos (1932), Above is Beginning Quote of the Last Chapter: Relativity and Modern Theories of the Universe -->

J.D. Bernal (1959/1969) Science in history Vol 3. p. 862; cited in: Ludwig von Bertalanffy (1968) General System Theory. p. 5-6