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EVOLUTION

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Originally appearing in Volume V10, Page 37 of the 1911 Encyclopedia Britannica.
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EVOLUTION  . The See also:

modern See also:doctrine of evolution or " evolving," as opposed to that of See also:simple creation, has been defined by Prof . See also:James See also:Sully in the 9th edition of this See also:encyclopaedia as a " natural See also:history of the cosmos including organic beings, ex-pressed in See also:physical terms as a See also:mechanical See also:process." The following exposition of the See also:historical development of the doctrine is taken from Sully's See also:article, and for the most See also:part is in his own words . In the modern doctrine of evolution the See also:cosmic See also:system appears as a natural product of elementary See also:matter and its See also:laws . The various grades of See also:life on our See also:planet are the natural consequencesof certain physical processes involved in the See also:gradual transformations of the See also:earth . Conscious life is viewed as conditioned by physical (organic and more especially See also:nervous) processes, and as evolving itself in See also:close correlation with organic evolution . Finally, human development, as exhibited in historical and pre-historical records, is regarded as the highest and most complex result of organic and physical evolution . This modern doctrine of evolution is but an expansion and completion of those physical theories (see below) which opened the history of See also:speculation . It differs from them in being grounded on exact and verified See also:research . As such, moreover, it is a much more limited theory of evolution than the See also:ancient . It does not necessarily concern itself about the question of the infinitude of worlds in space and in See also:time . It is content to explain the origin and course of development of the See also:world, the See also:solar or, at most, the sidereal system which falls under our own observation .

It would be difficult to say what branches of See also:

science had done most towards the See also:establishment of this doctrine . We must content ourselves by referring to the progress of physical (including chemical) theory, which has led to the See also:great generalization of the conservation of See also:energy; to the See also:discovery of the fundamental chemical identity of the matter of our planet and of other See also:celestial bodies, and of the chemical relations of organic and inorganic bodies; to the advance of astronomical speculation respecting the origin of the solar system, &c.; to the growth of the science of See also:geology which has necessitated the conception of vast and unimaginable periods of time in the past history of our globe, and to the rapid See also:march of the biological sciences which has made us See also:familiar with the simplest types and elements of organism; finally, to the development of the 'science of See also:anthropology (including See also:comparative psycho-logy, See also:philology, &c.), and to the vast See also:extension and improvement of all branches of historical study . History of the See also:Idea of Evolution.—The doctrine of evolution in its finished and definite See also:form is a modern product . It required for its formation an amount of scientific knowledge which could only be very gradually acquired . It is vain, therefore, to look for clearly defined and systematic presentations of the idea among ancient writers . On the other See also:hand, nearly all systems of See also:philosophy have discussed the underlying problems . Such questions as the origin of the cosmos as a whole, the See also:production of organic beings and of conscious minds, and the meaning of the observable grades of creation, have from the See also:dawn of speculation occupied men's minds; and the answers to these questions often imply a vague recognition of the idea of a gradual evolution of things . Accordingly, in tracing the antecedents of the modern philosophic doctrine we shall have to glance at most of the See also:principal systems of cosmology, ancient and modern . Yet since in these systems inquiries into the esse and fieri of the world are rarely distinguished with any precision, it will be necessary to indicate very briefly the See also:general outlines of the system so far as they are necessary for understanding their bearing on the problems of evolution . Mythological See also:Interpretation.—The problem of the origin of the world was the first to engage See also:man's speculative activity . Nor was this See also:line of inquiry pursued simply as a step in the more See also:practical problem of man's final destiny . The See also:order of ideas observable in See also:children suggests the reflection that man began to discuss the "whence " of existence before the "whither." At first, as in the See also:case of the See also:child, the problem of the See also:genesis of things was conceived anthropomorphically: the question " How did the world arise?" first shaped itself to the human mind under the form " Who made the world?" As See also:long as the problem was conceived in this simple manner there was, of course, no See also:room for the idea of a necessary self-conditioned evolution .

Yet the first indistinct germ of such an idea appears to emerge in See also:

combination with that of creation in some of the ancient systems of theogony . Thus, for example, in the myth of the ancient See also:Parsees, the gods Ormuzd and See also:Ahriman are said to evolve themselves out of a primordial matter . It may be sup-posed that these crude fancies embody a dim recognition of the physical forces and See also:objects personified under the forms of deities, and a See also:rude See also:attempt to See also:account for their genesis as a natural process . These first unscientific ideas of a genesis of the permanent objects of nature took as their See also:pattern the process of organic See also:reproduction and development, and this, not only because these objects were regarded as personalities, but also because this particular mode of becoming would most impress these See also:early observers . This same way of looking at the origin of the material world is illustrated in the See also:Egyptian notion of a cosmic See also:egg out of which issues the See also:god (Phta) who creates the world . See also:Indian Philosophy.—Passing from See also:mythology to speculation properly so called, we find in the early systems of philosophy of See also:India theories of See also:emanation which approach in some respects the idea of evolution . Brahma is conceived as the eternal self-existent being, which on its material See also:side unfolds itself to the world by gradually condensing itself to material objects through the gradations of See also:ether, See also:fire, See also:water, earth and the elements . At the same time this eternal being is conceived as the all-embracing world-soul from which emanates the See also:hierarchy of individual souls . In the later system of emanation of Sankhya there is a more marked approach to a materialistic doctrine of evolution . If, we are told, we follow the See also:chain of causes far enough back we reach unlimited eternal creative nature or matter . Out of this " principal thing " or " See also:original nature " all material and spiritual existence issues, and into it will return . Yet this primordial creative nature is endowed with volition with regard to its own development .

Its first emanation as plastic nature contains the original soul or deity out of which all individual souls issue . Early See also:

Greek Physicists.—Passing by See also:Buddhism, which, though teaching the periodic destruction of our world by fire, &c., does not seek to determine the ultimate origin of the cosmos, we come to those early Greek physical philosophers who distinctly set themselves to eliminate the idea of divine interference with the world by representing its origin and changes as a natural process . The early Ionian physicists, including Thales, Anaximander and Anaximenes, seek to explain the world as generated out of a primordial matter (Gr. i ? ; hence the name " Hylozoists "), which is at the same time the universal support of things . This substance is endowed with a generative or transmutative force by virtue of which it passes into a See also:succession of forms . They thus resemble modern evolutionists, since they regard the world with its See also:infinite variety of forms as issuing from a simple mode of matter . More especially the cosmology of Anaximander resembles the modern doctrine of evolution in its conception of the indeterminate (ro ibrerpov) out of which the particular forms of the cosmos are differentiated . Again, Anaximander may be said to prepare the way for more modern conceptions of material evolution by regarding his primordial substance as eternal, and by looking on all See also:generation as alternating with destruction, each step of the process being of course simply a transformation of the indestructible substance . Once more, the notion that this indeterminate See also:body contains potentially in itself the fundamental contraries—hot, See also:cold, &c.—by the See also:excretion or evolution of which definite substances were generated, is clearly a fore-casting of that See also:antithesis of potentiality and actuality which from See also:Aristotle downwards has been made the basis of so many theories of development . In conclusion, it is noteworthy that though resorting to utterly fanciful hypotheses respecting the order of the development of the world, Anaximander agrees with modern evolutionists in conceiving the heavenly bodies as arising out of an See also:aggregation of diffused matter, and in assigning to organic life an origin in the inorganic materials of the See also:primitive earth (pristine mud) . The doctrine of Anaximenes, who unites the conceptions of a determinate and indeterminate original substance adopted by Thales and Anaximander in the See also:hypothesis of a primordial and all-generating See also:air, is a clear advance on these theories, inasmuch as it introduces the scientific idea of condensation and rarefaction as the great generating or transforming agencies . For the See also:rest, his theory is c'iiefly important as emphasizing the vital See also:character of the original substance .

The primordial air is conceived as animated . Anaximenes seems to have inclined to a view of cosmic evolution as throughoutinvolving a quasi-spiritual See also:

factor . This idea of the air as the original principle and source of life and intelligence is much more clearly expressed by a later writer, See also:Diogenes of See also:Apollonia . Diogenes made this conception of a vital and intelligent air the ground of a teleological view of See also:climatic and atmospheric phenomena . It is noteworthy that he sought to establish the identity of organic and inorganic matter by help of the facts of vegetal and See also:animal See also:nutrition . Diogenes distinctly taught that the world is of finite duration, and will be renewed out of the primitive substance . Heraclitus again deserves a prominent See also:place in a history of the idea of evolution . Heraclitus conceives of the incessant process of See also:flux in which all things are involved as consisting of two sides or moments—generation and decay—which are regarded as a confluence of opposite streams . In thus making transition or See also:change, viewed as the identity of existence and non-existence, the leading idea of his system, Heraclitus anticipated in some measure See also:Hegel's See also:peculiar doctrine of evolution as a See also:dialectic process.' At the same time we may find expressed in figurative See also:language the germs of thoughts which enter into still newer doctrines of evolution . For example, the notion of conflict (r6Xeµos) as the See also:father of all things and of See also:harmony as arising out of a See also:union of discords, and again of an endeavour by individual things to maintain themselves in permanence against the universal process of destruction and renovation, cannot but remind one of certain fundamental ideas in See also:Darwin's theory of evolution . See also:Empedocles.—Empedocles took an important step in the direction of modern conceptions of physical evolution by teaching that all things arise, not by transformations of some primitive form of matter, but by various combinations of a number of permanent elements . Further, by maintaining that the elements are continually being combined and separated by the two forces love and hatred, which appear to represent in a figurative way the physical forces of attraction and repulsion, Empedocles may be said to have made a considerable advance in the construction of the idea of evolution as a strictly mechanical process .

It may be observed, too, that the hypothesis of a primitive compact See also:

mass (sphaerus), in which love (attraction) is supreme, has some curious points of similarity to, and contrast with, that notion of a primitive nebulous matter with which the modern doctrine of cosmic evolution usually sets out . Empedocles tries to explain the genesis of organic beings, and, according to See also:Lange, anticipates the idea of Darwin that adaptations abound, because it is their nature to perpetuate themselves . He further recognizes a progress in the production of See also:vegetable and animal forms, though this part of his theory is essentially crude and unscientific . More important in relation to the modern problems of evolution is his thoroughly materialistic way of explaining the origin of sensation and knowledge by help of his peculiar hypothesis of effluvia and pores . The supposition that sensation thus rests on a material process of absorption from See also:external bodies naturally led up to the idea that See also:plants and even inorganic subtances are precipient, and so to an indistinct recognition of organic life as a See also:scale of intelligence . Atomists.—In the theory of Atomism taught by Leucippus and See also:Democritus we have the basis of the modern mechanical conceptions of cosmic evolution . Here the endless harmonious diversity of our cosmos, as well as of other worlds supposed to coexist with our own, is said to arise through the various combination of indivisible material elements differing in figure and magnitude only . The force which brings the atoms together in the forms of objects is inherent in the elements, and all their motions are necessary . The origin of things, which is also their substance, is thus laid in the simplest and most homogeneous elements or principles . The real world thus arising consists only of diverse combinations of atoms, having the properties of magnitude, figure, See also:weight and hardness, all other qualities being relative only to the sentient organism . The problem of the genesis of mind is practically solved by identifying the soul, ' This is brought out by F . See also:Lassalle, See also:Die Philosophic Herakleitos, p .

126 . or vital principle, with See also:

heat or fire which pervades in unequal proportions, not only man and animals, but plants and nature as a whole, and through the agitation of which by incoming effluvia all sensation arises . Aristotle.—Aristotle is much nearer a conception of evolution than his See also:master See also:Plato . It is true he sets out with a transcendent Deity, and follows Plato in viewing the creation of the cosmos as a process of descent from the more to the less perfect according to the distance from the original self-moving agency . Yet on the whole Aristotle leans to a teleological theory of evolution, which he interprets dualistually by means of certain See also:meta-physical distinctions . Thus even his idea of the relation of the divine activity to the world shows a tendency to a pantheistic notion of a divine thought which gradually realizes itself in the process of becoming . Aristotle's distinction of form and matter, and his conception of becoming as a transition from actuality to potentiality, provides a new ontological way of conceiving the process of material and organic evolution." To Aristotle the whole of nature is See also:instinct with a vital impulse towards some higher manifestation . Organic life presents itself to him as a progressive scale of complexity determined by its final end, namely, man ? In some respects Aristotle approaches the modern view of evolution . Thus, though he looked on See also:species as fixed, being the realization of an unchanging formative principle (See also:ghats), he seems, as See also:Ueberweg observes, to have inclined to entertain the possibility of a spontaneous generation in the case of the lowest organisms . Aristotle's teleological conception of organic evolution often approaches modern mechanical conceptions . Thus he says that nature fashions See also:organs in the order of their See also:necessity, the first being those essential to life .

So, too, in his See also:

psychology he speaks of the several degrees of mind as arising according to a progressive necessity .3 In his view of See also:touch and See also:taste, as the two fundamental and essential senses, he may remind one of See also:Herbert See also:Spencer's doctrine . At the same time Aristotle precludes the idea of a natural development of the See also:mental See also:series by the supposition that man contains, over and above a natural finite soul inseparable from the body, a substantial and eternal principle (vas) which enters into the individual from without . Aristotle's brief suggestions respecting the origin of society and governments in the Politics show a leaning to a naturalistic interpretation of human history as a development conditioned by growing necessities . Strato.—Of Aristotle's immediate successors one deserves to be noticed here, namely, Strato of See also:Lampsacus, who See also:developed his master's cosmology into a system of See also:naturalism . Strato appears to reject Aristotle's idea of an original source of See also:movement and life extraneous to the world in favour of an immanent principle . All parts of matter have an inward plastic life whereby they can See also:fashion themselves to the best See also:advantage, according to their capability, though not with consciousness . The See also:Stoics.—In the cosmology of the Stoics we have the germ of a monistic and pantheistic conception of evolution . All things are said to be developed out of an original, being, which is at once material (fire) and spiritual (the Deity), and in turn they will dissolve back into this primordial source . At the same time the world as a developed whole is regarded as an organism which is permeated with the divine Spirit, and so we may say that the world-process is a self-realization of the divine Being . The formative principle or force of the world is said to contain the several rational germinal forms of things . Individual things are sup-posed to arise out of the original being, as animals and plants out of seeds . Individual souls are an efflux from the all-compassing world-soul .

The necessity in the world's order is regarded by the Stoics as identical with the divine See also:

reason, and this idea is used as the basis of a teleological and optimistic view of nature . Very curious, in relation to modern evolutional ideas, is the Stoical doctrine that our world is but one of a series of exactly " See also:Zeller says that through this distinction Aristotle first made possible the idea of development . s See this well brought out in G . H . See also:Lewes's Aristotle, p . 187 . 1 See also:Grote calls See also:attention to the contrast between Plato's and Aristotle's way of conceiving the gradations of mind (Aristotle, ii . 170.identical ones, all of which are destined to be burnt up and destroyed . The Epicureans—See also:Lucretius.—The Epicureans differed from the Stoics by adopting a purely mechanical view of the world-process . Their fundamental conception is that of Democritus; they seek to account for the formation of the cosmos, with its order and regularity, by setting out with the idea of an original (See also:vertical) See also:motion of the atoms, which somehow or other results in movements towards and from one another . Our world is but one of an infinite number of others, and all the harmonies and adaptations of the universe are regarded as a See also:special case of the infinite possibilities of mechanical events . Lucretius regards the primitive atoms (first beginnings or first bodies) as seeds out of which individual things are developed .

All living and sentient things are formed out of insentient atoms (e.g. See also:

worms See also:spring out of dung) . The peculiarity of organic and sentient bodies is due to the minuteness and shape of their particles, and to their special motions and combinations . So, too, mind consists but of extremely See also:fine particles of matter, and dissolves into air when the body See also:dies . Lucretius traces, in the fifth See also:book of his poem, the progressive genesis of vegetal and animal forms out of the See also:mother-earth . He vaguely anticipates the modern idea of the world as a survival of the fittest when he says that many races may have lived and died out, and that those which still exist have been protected either by See also:craft, courage or See also:speed . Lucretius touches on the development of man out of a primitive, See also:hardy, beast-like See also:condition . Pregnant hints are given respecting a natural development of language which has its germs in sounds of quadrupeds and birds, of religious ideas out of dreams and waking hallucinations, and of the See also:art of See also:music by help of the See also:suggestion of natural sounds . Lucretius thus recognizes the whole range of existence to which the doctrine of evolution may be applied . Neoplatonists.—In the doctrines of the Neoplatonists, of whom See also:Plotinus is the most important, we have the world-process represented after the example of Plato as a series of descending steps, each being less perfect than its predecessors, since it is further removed from the first cause.4 The system of Plotinus, Zellar remarks, is not strictly speaking one of emanation, since there is no communication of the divine essence to the created world; yet it resembles emanation inasmuch as the genesis of the world is conceived as a necessary physical effect, and not as the result of volition . In See also:Proclus we find this conception of an emanation of the world out of the Deity, or the See also:absolute, made more exact, the process being regarded as threefold—(1) persistence of cause in effect, (2) the departure of effect from cause, and (3) the tendency of effect to revert to its cause . The Fathers.—The speculations of the fathers respecting the origin and course of the world seek to combine See also:Christian ideas of the Deity with doctrines of Greek philosophy . The See also:common idea of the origin of things is that of an absolute creation of matter and mind alike .

The course of human history is regarded by those writers who are most concerned to refute Judaism as a progressive divine See also:

education . Among the Gnostics we meet with the hypothesis of emanation, as, for example, in the curious cosmic theory of See also:Valentinus . See also:Middle Ages—Early Schoolmen.—In the speculative writings of the middle ages, including those of the schoolmen, we find no progress towards a more accurate and scientific view of nature . The cosmology of this See also:period consists for the most part of the Aristotelian teleological view of nature combined with the Christian idea of the Deity and His relation to the world . In certain writers, however, there appears a more elaborate trans-formation of the doctrine of creation into a system of emanation . According to See also:John Scotus See also:Erigena, the nothing out of which the world is created is the divine essence . Creation is the See also:act by which God passes through the primordial causes, or universal ideas, into the region of particular things (processio), in order finally to return to himself (reversio) . The transition from the 4 Zeller observes that this scale of decreasing perfection is a necessary consequence of the idea of a transcendent deity . universal to the particular is of course conceived as a descent or degradation . A similar doctrine of emanation is to be found in the writings of Bernhard of See also:Chartres, who conceives the process of the unfolding of the world as a movement in a circle from the most general to the individual, and from this back to the most general . This movement is said to go forth from God to the animated See also:heaven, stars, visible world and man, which represent decreasing degrees of See also:cognition . Arab Philosophers.—Elaborate doctrines of emanation, largely based on Neoplatonic ideas, are also propounded by some of the Arabic philosophers, as by See also:Farabi and See also:Avicenna .

The leading thought is that of a descending series of intelligences, each emanating from its predecessor, and having its appropriate region in the universe . Jewish Philosophy.—In the Jewish speculations of the middle ages may be .found curious forms of the doctrine of emanations uniting the Biblical idea of creation with elements See also:

drawn from the Persians and the Greeks . In the later and developed form of the Kabbala, the origin of the world is represented as a gradually descending emanation of the See also:lower out of the higher . Among the philosophic See also:Jews, the See also:Spanish Avicebron, in his Fons Vitae, expounds a curious doctrine of emanation . Here the divine will is viewed as an efflux from the divine See also:wisdom, as the inter-mediate See also:link between God, the first substance, and all things, and as the See also:fountain out of which all forms emanate . At the same time all forms, including the higher intelligible ones, are said to have their existence only in matter . Matter is the one universal substance, body and mind being merely specifications of this . Thus Avicebron approaches, as Salomon Munk observes,' a pantheistic conception of the world, though he distinctly denies both matter and form to God . Later Scholastics.—Passing now to the later` schoolmen, a See also:bare mention must be made of See also:Thomas See also:Aquinas, who elaborately argues for the absolute creation of the world out of nothing, and of Albertus See also:Magnus, who reasons against the Aristotelian idea of the past eternity of the world . More importance attaches to See also:Duns Scotus, who brings prominently forward the idea of a progressive development in nature by means of a process of determination . The original substance of the world is the materia primo-prima, which is the immediate creation of the Deity . This serves Duns Scotus as the most universal basis of existence, all angels having material bodies .

This matter is differentiated into particular things (which are not privations but perfections) through the addition of an individualizing principle (haecceitas) to the universal (quidditas) . The whole world is represented by the figure of a See also:

tree, of which the seeds and roots are the first indeterminate matter, the leaves the accidents, the twigs and branches corruptible creatures, the blossoms the rational soul, and the See also:fruit pure See also:spirits or angels . It is also described as a bifurcation of two twigs, mental and bodily creation out of a common See also:root . One might almost say that Duns Scotus recognizes the principle of a gradual physical evolution, only that he chooses to represent the mechanism by which the process is brought about by means of See also:quaint scholastic See also:fictions . Revival of Learning.—The period of the revival of learning, which was also that of a renewed study of nature, is marked by a considerable amount of speculation respecting the origin of the universe . In some of these we see a return to Greek theories, though the See also:influence of physical discoveries, more especially those of See also:Copernicus, See also:Kepler and Galileo, is distinctly traceable . See also:Telesio.—An example of a return to early Greek speculation is to be met with in Bernardino Telesio . By this writer the world is explained as a product of three principles—dead matter, and two active forces, heat and cold . Terrestrial things arise through a confluence of heat, which issues from the heavens, and cold, which comes from the earth . Both principles have sensibility, and thus all products of their collision are sentient, that is, feel See also:pleasure and See also:pain . The superiority of animals to plants and metals in the See also:possession of special organs of sense is connected with the greater complexity and heterogeneity of their structure . ' Melanges de philosophic juive et arabe, p .

225 . See also:

Giordano See also:Bruno.—In the system of Giordano Bruno, who sought to construct a philosophy of nature on the basis of new scientific ideas, more particularly the doctrine of Copernicus, we find the outlines of a theory of cosmic evolution conceived as an essentially vital process . Matter and form are here identified, and the evolution of the world is presented as the unfolding of the world-spirit to its perfect forms according to the plastic substratum (matter) which is but one of its sides . This process of change is conceived as a transformation, in See also:appearance only, of the real unchanging substance (matter and form) . All parts of matter are capable of developing into all forms; thus the materials of the table and See also:chair may under proper circumstances be developed to the life of the plant or of the animal . The elementary parts of existence are the minima, or monads, which are at once material and mental . On their material side they are not absolutely unextended, but spherical . Bruno looked on our solar system as but one out of an infinite number of worlds . His theory of evolution is essentially pantheistic, and he does not employ his hypothesis of monads in order to See also:work out a more mechanical conception . See also:Campanella.—A word must be given to one of Bruno's See also:con-temporary compatriots, namely Campanella, who gave poetic expression to that system of universal vitalism which Bruno developed . He argues, from the principle quicquid est in effectibus else et in causis, that the elements and the whole world have sensation, and thus he appears to derive the organic part of nature out of the so-called " inorganic." See also:Boehme.—Another writer of this transition period deserves a passing reference here, namely, See also:Jacob Boehme the mystic, who by his conception of a process of inner diremption as the essential character of all mind, and so of God, prepared the way for later See also:German theories of the origin of the world as the self-differentiation and self-externalization of the absolute spirit . See also:Hobbes and Gassendi.—The influence of an advancing study of nature, which was stimulated if not guided by See also:Bacon's writings, is seen in the more careful doctrines of See also:materialism worked out almost simultaneously by Hobbes and Gassendi .

These theories, however, contain little that bears directly on the hypothesis of a natural evolution of things . In the view of Hobbes, the difficulty of the genesis of conscious minds is solved by saying that sensation and thought are part of the reaction of the See also:

organ-ism on external movement .. Yet Hobbes appears (as See also:Clarke points out) to have vaguely See also:felt the difficulty; and in a passage of his Physics (See also:chap . 25, See also:sect . 5) he says that the universal existence of sensation in matter cannot be disproved, though he shows that when there are no organic arrangements the mental side of the movement (phantasma) is evanescent . The theory of the origin of society put forth by Hobbes, though directly opposed in most respects to modern ideas of social evolution, deserves mention here by reason of its enforcing that principle of struggle (bellum omnium contra omnes) which has played so conspicuous a part in the modern doctrine of evolution . Gassendi, with some deviations, follows See also:Epicurus in his theory of the formation of the world . The world consists of a finite number of atoms, which have in their own nature a self-moving force or principle . These atoms, which are the seeds of all things, are, however, not eternal but created by God . Gassendi distinctly argues against the existence of a world-soul or a principle of life in nature . See also:Descartes.—In the philosophy of Descartes we meet with a See also:dualism of mind and matter which does not easily lend itself to the conception of evolution . His doctrine that consciousness is confined to man, the lower animals being unconscious See also:machines (automata), excludes all idea of a progressive develcpment of mind .

Yet Descartes, in his Principia Philosophiae, laid the See also:

foundation of the modern mechanical conception of nature and of physical evolution . In the third part of this work he inclines to a thoroughly natural hypothesis respecting the genesis of the physical world, and adds in the See also:fourth part that the same See also:kind of explanation might be applied to the nature and formation of plants and animals . He is indeed careful to keep right with the orthodox doctrine of creation by saying that he does not believe the world actually arose in this mechanical way out of the three kinds of elements which he here supposes, but that he simply puts out his hypothesis as a mode of conceiving how it might have arisen . Descartes's account of the mind and its passions is thoroughly materialistic, and to this extent he See also:works in the direction of a materialistic explanation of the origin of mental life . See also:Spinoza.—In Spinoza's pantheistic theory of the world, which regards thought and extension as but two sides of one substance, the problem of becoming is submerged in that of being . Al-though Spinoza's theory attributes a mental side to all physical events, he rejects all teleological conceptions and explains the order of things as the result of an inherent necessity . He recognizes gradations of things according to the degree of complexity of their movements and that of their conceptions . To Spinoza (as Kuno See also:Fischer observes) man differs from the rest of nature in the degree only and not in the kind of his See also:powers . So far Spinoza approaches the conception of evolution . He may be said to furnish a further contribution to a metaphysical conception of evolution in his view of all finite individual things as the infinite variety to which the unlimited productive See also:power of the universal substance gives See also:birth . See also:Sir F . See also:Pollock has taken pains to show how nearly Spinoza approaches certain ideas contained in the modern doctrine of evolution, as for example that of self-preservation as the determining force in things .

See also:

Locke.—In Locke we find, with a retention of certain .See also:anti-evolutionist ideas, a marked tendency to this mode'of viewing the world . To Locke the universe is the result of a See also:direct act of creation, even matter being limited in duration and created . Even if matter were eternal it would, he thinks, be incapable of producing motion; and if motion is itself conceived as eternal, thought can never begin to be . The first eternal being is thus spiritual or " cogitative," and contains in itself all the perfections that can ever after exist . He repeatedly insists on the impossibility of senseless matter putting on sense.' Yet while thus placing himself at a point of view opposed to that of a gradual evolution of the organic world, Locke prepared the way for this doctrine in more ways than one . First of all, his genetic method as applied to the mind's ideas—which laid the See also:foundations of See also:English See also:analytical psychology—was a step in the direction of a conception of mental life as a gradual evolution . Again he works towards the same end in his celebrated refutation of the scholastic theory of real specific essences . In this See also:argument he emphasizes the vagueness of the boundaries which See also:mark off organic species with a view to show that these do not correspond to absolutely fixed divisions in the See also:objective world, that they are made by the mind, not by nature.2 This idea of the continuity of species is developed more fully in a remarkable passage (See also:Essay, bk. iii. ch. vi . § 12), where he is arguing in favour of the hypothesis, afterwards elaborated by See also:Leibnitz, of a graduated series of minds (species of spirits) from the Deity down to the lowest animal intelligence . He here observes that " all quite down from us the descent is by easy steps, and a continued series of things, that in each remove differ very little from one another." Thus man approaches the beasts, and the animal See also:kingdom is nearly joined with the vegetable, and so on down to the lowest and " most inorganical parts of matter." Finally, it is to be observed that Locke had a singularly clear view of organic arrangements (which of course he explained according to a theistic See also:teleology) as an See also:adaptation to the circumstances of the environment or to " the neighbourhood of the bodies that surround us." Thus he suggests that man has not eyes of a microscopic delicacy, because he would receive no great advantage from such acute organs, since though adding indefinitely to his speculative knowledge of the physical world they would ' Yet he leaves open the question whether the Deity has annexed thought to matter as a See also:faculty, or whether it rests on a distinct spiritual principle . 2 Locke See also:half playfully touches on certain monsters, with respect to which it is difficult to determine whether they ought to be called men . (Essay, book iii. ch. vi. sect .

26, 27.)not practically benefit their possessor (e.g. by enabling him to avoid things at a convenient distance).' Idea of Progress in History.—Before leaving the 17th See also:

century we must just refer to the writers who laid the foundations of the essentially modern conception of human history as a gradual upward progress . According to See also:Flint,' there were four men who in this and the preceding century seized and made prominent this idea, namely, See also:Bodin, Bacon, Descartes and See also:Pascal . The former distinctly argues against the idea of a deterioration of man in the past . In this way we see that just as advancing natural science was preparing the way for a doctrine of physical evolution, so advancing historical research was leading to the application of a similar idea to the collective human life . English Writers of the r8th Century—See also:Hume.—The theological discussions, which make up so large a part of the English speculation of the 18th century cannot detain us here . There is, however, one writer who sets forth so clearly the a'ternative suppositions respecting the origin of the world that he claims a brief See also:notice . We refer to See also:David Hume . In his Dialogues concerning Natural See also:Religion he puts forward tentatively, in the See also:person of one of his interlocutors, the ancient hypothesis that since the world resembles an animal or vegetal organism rather than a See also:machine, it might more easily be accounted for by a process of generation than by an act of creation . Later on he develops the materialistic view of Epicurus, only modifying it so far as to conceive of matter as finite . Since a finite number of particles is only susceptible of finite transpositions, it must happen (he says), in an eternal duration, that every possible order or position will be tried an infinite number of times, and hence this world is to be regarded (as the Stoics maintained) as an exact reproduction of previous worlds . The See also:speaker seeks to make intelligible the appearance of art and contrivance in the world as a result of a natural See also:settlement of the universe (which passes through a succession of chaotic conditions) into a See also:stable condition, having a constancy in its forms, yet without its several parts losing their motion and fluctuation . See also: