"Light is the living substance of Mind in action. It is the creating principle of the One substance.

The One substance is the etheric "spiritual" substance of the One universal Mind.

The entire "created" universe of all that is, ever has been, or ever will be, is but the One substance in motion, light."

"The material substance of Mind is an all pervading ether which is indivisible, inseparable, indestructible, unalterable and unchangedable; but potentially it contains the appearance of all these dimensions of separability in the states of motion which register the dynamic process of thinking.

 The words "spirit" and "ether" are used to express the tenuity of the dimensionless universe, as "solidity" is used to express the compactness of the apparently measurable universe."

"The temperature in the wake of the steamer is higher than that of the surrounding water. Similarly the temperature of the spiral nebula is higher than that of the surrounding "ether" matter, because of the heat energy generated by thinking and transferred to the whirling spheres."

"When giant suns have radiated their heat to the absolute zero of the surrounding ether substance of Mind, they cease all appearance of individual existence. Their forms have disappeared with the cessation of motion, but their substance is as eternal as Mind is eternal."

"Man's speed of light is the speed at which that state of motion-in-opposition, known as incandescent luminosity appears to travel through those high octaves of integrating matter which man calls "empty space," or the "ether of space." This measure of light is but the high measure of a great range of apparent speeds."

"The ecstasy of my thinking varies the spectra of ten times ten billion stars and illumines the ether of endless space."

"Man has to do with illusion during those periods in which he is forming the idea of himself as illusion; so, therefore, it is necessary that he shall understand the dimensions of the universe of illusion in order that he may control them.

 Man has long ago discarded the corpuscular theory of light in favor of a theory of electromagnetic effect of undulating waves which are supposed to exist in the ether.

 He must now replace this second theory, for the ether of man's concept is non-existent. There are no undulating ether waves.

 Light is corpuscular."

Russell, The Universal One