224 DESIGN IN NATURE 



between the ruins of the worlds that have been and the chaotic materials of the worlds that shall be ; and, in spite 

 of all waste and destruction, Cosmos is extending his borders at the expense of Chaos." 



The following is Mr. Herbert Spencer's view of this very interesting and difficult subject : " Throughout the 

 universe in generll, and in detail, there is an unceasing redistribution of matter and motion. This redistribution 

 constitutes evolution when there is a predominant integration of matter and dissipation of motion, and constitutes 

 dissolution when there is a predominant absorption of motion and disintegration of matter. Evolution is simple 

 when the process of integration, or the formation of a coherent aggregate, proceeds uncomplicated by other processes. 

 Evolution is compound when, along with this primary change from an incoherent to a coherent state, there go on 

 secondary changes due to differences in the circumstances of the different parts of the aggregate. 



" These secondary changes constitute a transformation of the homogeneous into the heterogeneous-a transforma- 

 tion which Uke the first, is exhibited in the universe as a whole, and in all (or nearly all) its details ; m the aggre- 

 gate of stars and nebulae ; in the planetary system ; in the earth as an inorganic mass ; m each organism, vegetal 

 or animal ; in the aggregate of organisms throughout geologic time ; in the mmd ; in society ; in all products of 



social activity. . , , r vrv ,• ,■ 



" The process of integration, acting locally as well as generally, combines with the process of differentiation 

 to render this change not simply from homogeneity to heterogeneity, but from an indefinite homogeneity to a defimte 

 heterogeneity ; and this trait of increasing definiteness, which accompanies the trait of increasing heterogeneity, 

 is, hke it, exhibited in the totaUty of things, and in all its divisions and subdivisions down to the minutest. 



" Along with this redistribution of the matter composing any evolving aggregate there goes on a redistribution 

 of the retained motion of its components in relation to one another ; this also becomes, step by step, more definitely 

 heterogeneous. . . . This rhythm of evolution and dissolution, completing itself during short periods in small aggre- 

 gates, "and in the vast aggregates distributed through space completing itself in periods immeasurable by human 

 thought, is, so far as we can see, universal and eternal. . . . All these phenomena, from their great features down to 

 their minutest details, are necessary results of the persistence of force under its forms of matter and motion. Given 

 these as distributed through space, and their quantities being unchangeable, either by increase or decrease, there 

 inevitably result the continuous redistributions distinguishable as evolution and dissolution, as well as all these 

 special traits above enumerated. That which persists unchanging in quantity, but ever changing in form, under 

 these sensible appearances which the universe presents to us, transcends human knowledge and conception— is 

 an unknown and unknowable power, which we are obhged to recognise as without hmit in space and without 

 beginning or end in time." 



It will be observed that, in Immanuel Kant's and Herbert Spencer's systems of the universe, matter and a 

 power of attraction and condensation and of repulsion and disintegration are taken for granted ; this power con- 

 verting homogeneous masses into heterogeneous masses at one period, and heterogeneous masses into homogeneous 

 masses at another period. The homogeneity and heterogeneity are applied to the inorganic and organic kingdoms 

 alike. Heterogeneity is held to be another term for differentiation, and differentiation apphes to the structure 

 of the universe as a whole, and to plants and animals as integral parts of it. Two things are to be considered in 

 this connection. First, can mere attraction and condensation convert strictly homogeneous substances into hete- 

 rogeneous ones ; and second, can mere physical heterogeneity, unaided, produce differentiation and division of 

 labour in plants and animals ? This is a subject of the greatest possible importance, for on it hinges the existence 

 or non-existence of a large number of elements in the inorganic kingdom, and a large number of different substances 

 in the organic kingdom, not only in the embryonic but also in the young and adult states. One can readily con- 

 ceive a highly heated molten mass where the elements of the universe are blended, and apparently form a homo- 

 geneous whole. Similarly in reproduction the germ, seed, and egg may consist of apparently homogeneous and 

 identical matter, but (and the bid has great significance in the present case) are the elements annihilated by mere 

 superheating, or can elements, if they do not exist in the molten mass, be obtained from it by mere aggregation, con- 

 densation, and cooling ? In like manner, are the potentialities and dormant powers of the germ, seed, and egg 

 destroyed by being reduced to a molecular mass, or can the various tissues, soft, hard, and otherwise, of the body 

 be developed from the germ, seed, and egg as apart from latent or actual heterogeneity therein ? I do not think 

 they can. I am disposed to believe that much confusion has been introduced into the consideration of the inorganic 

 and organic kingdoms by the lax use of the terms homogeneity, heterogeneity, and differentiation. If a thing 

 be absolutely homogeneous and identical in all its parts and particles it cannot, strictly speaking, be converted by 

 any physical process into a heterogeneous substance. Neither can a heterogeneous substance be converted into a 

 simple homogeneous one. They are the opposites of each other. Mere heterogeneity, on the other hand, does 

 not result in differentiation from the botanical and zoological points of view. To differentiate in biology is to 

 produce different substances, structures, and organs discharging dissimilar functions. This involves life, a First 



