But, further! It is highly probable that life of any kind can only originate in the dark. Certainly, conception invariably takes place in complete darkness, and the whole period of embryonic development is passed in that condition. Again, inter-stellar space is, of course, absolutely black and devoid of any form of light save the faint twinklings of the far-off stars. Without the surface of some globe to reflect the sun's rays, no light of any kind would be possible; so that if life were conveyed across space, from star to star, upon infinitesimal specks of dust, under the influence of light pressure, as postulated by Arrhenius (_Worlds in the Making_, pp. 212-30), this life must exist, and in a sense originate, in the blackness of inter-stellar space.[10] And, finally, if life on our globe originated, as many think, in the ocean's depths,[11] this must have been in the densest darkness, since light penetrates but a few fathoms below the surface of the ocean. Below that all is blackness, complete and eternal. No light penetrates to that depth--nor has it for millions of years! Yet it is in this region that life is thought to have originated! As G. W. Warder expressed it (_The Universe a Vast Electric Organism_, pp. 60-1): "During this period of primeval 'darkness upon the face of the waters' the resistless electric waves of the sun were beating upon the cloud-enwrapped surface of the planet. It was the formative period of elementary life, and the descendants and successors of that mighty host of living beings have to this day to lay the foundations of their being in similar conditions of darkness. _Creative energy in its first stages of living form operates in dense darkness_, and the first life upon the planet began and perfected itself in the age when midnight gloom enveloped the globe." This fact--that life originated in darkness, and that the power of life can only be exercised in darkness--is, it seems to me, a most significant one when viewed in the light of our studies, and seems to point to the conclusion that the "darkness" said to be essential at spiritistic circles is indeed necessary; and that, when delicate and subtle forms of life and energy are being manifested, they are likely to become disrupted by the sudden introjection of a coarse and powerful form of energy, such as light, so that this "condition," said to be necessary by all mediums, is probably in reality essential; and their claim, far from being absurd, is well founded, and in accordance with well-established scientific facts. 17. So far as to the physical phenomena. We must now turn to the mental manifestations, and discuss one or two points in connection with them before concluding.