As the vortex theory accounts for the formation of the inorganic world, so does biology account for the formation of the living organism. That also has its origin in a primary nucleus which, as soon as it is established, operates as a centre of attraction for the formation of all those physical organs of which the perfect individual is composed. The science of embryology shows that this rule holds good without exception throughout the whole range of the animal world, including man; and botany shows the same principle at work throughout the vegetable world. All branches of physical science demonstrate the fact that every completed manifestation, of whatever kind and on whatever scale, is started by the establishment of a nucleus, infinitely small but endowed with an unquenchable energy of attraction, causing it to steadily increase in power and definiteness of purpose, until the process of growth is completed and the matured form stands out as an accomplished fact. Now if this be the universal method of Nature, there is nothing unnatural in supposing that it must begin its operation at a stage further back than the formation of the material nucleus. As soon as that is called into being it begins to operate by the law of attraction on the material plane; but what is the force which originates the material nucleus? Let a recent work on physical science give us the answer; "In its ultimate essence, energy may be incomprehensible by us except as an exhibition of the direct operation of that which we call Mind or Will." The quotation is from a course of lectures on "Waves in Water, Air and Æther," delivered in 1902, at the Royal Institution, by J. A. Fleming. Here, then, is the testimony of physical science that the originating energy is Mind or Will; and we are, therefore, not only making a logical deduction from certain unavoidable intuitions of the human mind, but are also following on the lines of the most advanced physical science, when we say that the action of Mind plants that nucleus which, if allowed to grow undisturbed, will eventually attract to itself all the conditions necessary for its manifestation in outward visible form. Now the only action of Mind is Thought; and it is for this reason that by our thoughts we create corresponding external conditions, because we thereby create the nucleus which attracts to itself its own correspondences in due order until the finished work is manifested on the external plane. This is according to the strictly scientific conception of the universal law of growth; and we may therefore briefly sum up the whole argument by saying that our thought of anything forms a spiritual prototype of it, thus constituting a nucleus or centre of attraction for all conditions necessary to its eventual externalization by a law of growth inherent in the prototype itself. VI. THE LAW OF GROWTH.