In Isis Unveiled we wrote that which we now repeat: "We are at the bottom of a cycle and evidently in a transitory state. Plato divides the intellectual progress of the universe during every cycle into fertile and barren periods. In the sublunary regions, the spheres of the various elements remain eternally in perfect harmony with the divine nature, he says, 'but their parts,' owing to a too close proximity to earth, and their commingling with the earthly (which is matter, and therefore the realm of evil), 'are sometimes according, and sometimes contrary to (divine) nature.' When those circulations – which Eliphas Levi calls ' currents of the astral light' – in the universal ether which contains in itself every element, take place in harmony with the divine spirit, our earth and everything pertaining to it enjoys a fertile period. The occult powers of plants, animals, and minerals magically sympathize with the 'superior natures,' and the divine soul of man is in perfect intelligence with these 'inferior' ones. But during the barren periods, the latter lose their magic sympathy, and the spiritual sight of the majority of mankind is so blinded as to lose every notion of the superior powers of its own divine spirit. We are in a barren period: the eighteenth century, during which the malignant fever of scepticism broke out so irrepressibly, has entailed unbelief as an hereditary disease upon the nineteenth. The divine intellect is veiled in man; his animal brain alone philosophizes." And philosophizing alone, how can it understand the "SOUL DOCTRINE"?

H. P. Blavatsky
The Secret Doctrine, ii 70–74