"Mind is the universe. Mind substance is "spiritual" substance. Spirit is light. Spirit is the ultimate, the eternal, though finite substance. Spirit is not infinite. Nothing in this universe of motion is infinite. Man's concept of an infinite God, possessing infinite knowledge and infinite power, Creator of an infinite universe of infinite extension, is not in accord with the laws of motion. This is a boundless, eternal, dimensionless universe of definite limitations both as to cause and to all effects of cause. Dimension is an illusion of relation of effects, which are in themselves but illusions." Russell, The Universal One, p. 2.
"Dimension (limits) is an illusion of relation of EFFECTS, which are in themselves but illusions." Dimensions = limits = effects = illusion. (emphasis is mine.) In other words there is no "thing" in existence other than Mind which in itself is only a state of being or awareness - not a physical thing. Keyword in this phrase is "relation" which may be considered or used as "delta" in engineering or "interval" in music. It is the "ratio" or "relativity" (one to another)." Dale Pond