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 10 EVOLUTION party is allowed to an almost unlimited extent, and the privilege is often used to pervert ra- ther than elicit the truth. It would be difficult to fix a precise limit of restriction, as it neces- sarily rests very much in the discretion of the court ; but the prevailing practice seems to be suited rather to a remote period, when from the disorders of society and consequent laxity of moral principle there was little reli- ance to be placed on the oath of witnesses, than to the present advanced state of social order. EVOLUTION, the term now generally applied to the doctrine that the existing universe has been gradually unfolded by the action of natu- ral causes in the immeasurable course of past time. The question how the present order of things originated seems natural to the human mind, and has been put by all the races of men. The answer given in their cosmogonies, that it was created as we now see it by super- natural power, has been generally accepted as a matter of religious faith. The early Greek philosophers first brought the question into the field of speculation, and taught that all natural things have sprung from certain primal ele- ments, such as air, water, or fire. As regards the origin of life, Anaximander is said to have held that animals were begotten from earth by means of moisture and heat, and that man did not originate in a perfectly developed state, but was engendered from beings of a different form. Empedocles taught that the various parts of animals, arms, feet, eyes, &c., existed separately at first ; that they combined grad- ually, and that these combinations, capable of subsisting, survived and propagated them- selves. Anaxagoras believed that plants and animals owe their origin to the fecundation of the earth whence they sprung by germs con- tained in the air. Aristotle, the father of natu- ral history, entertained much more rational views upon the subject, and it is maintained that he held opinions as to the causes of di- versity in living beings similar to those that are entertained by the latest zoologists. It has been asserted that some of the early theolo- gians, including St. Augustine and St. Thomas Aquinas, announced doctrines that harmonize apparently with the modern views of evolu- tion. We however find no development of the ideas thus shadowed forth. Linnaeus and Buf- fon seem to have been the first among modern naturalists who formed definite conceptions of a progressive organic development, but they did little to elucidate the idea. Immanuel Kant announced in 1755 his theory of the me- chanical origin of the universe, and supposed that the different classes of organisms are re- lated to each other through generation from a common original germ. Dr. Erasmus Darwin, grandfather of Charles Darwin, in his Zoono- mia (1794), maintained the natural genesis of organic beings. But the first to frame a dis- tinct hypothesis of development was Lamarck, who published his Philosophic zoologique in 1809, and developed his views still further in 1815 in his Histoire naturale des animaux sans vertebres. He held that all organic forms, from the lowest to the highest, have been developed progressively from living microscopic particles. Similar conclusions were arrived at by Goethe in Germany, and by Geoffroy Saint-Hilaire in France in his work Sur le principe de Vunite de composition organique, published in 1828. The views thus far were of a general and high- ly speculative nature, and without firm scien- tific ground-work. It was only when the ques- tion was narrowed down to that of the muta- bility or immutability of species, and to the causes and extent of variation as determined by observation and experiment, that the real difficulties of the case were grappled with, and the inquiry assumed a strictly scientific char- acter. In 1813 Dr. W. 0. Wells read a paper before the London royal society, in which he recognized distinctly the principle of natural se- lection as applied to certain races of mankind, In 1822 the Rev. William Herbert, afterward dean of Manchester, declared his conviction that " botanical species are only a higher and more permanent class of varieties;" and he extended this opinion to animals. Leopold von Buch, in his Physilcalische Beschreibung del Canarischen Inseln (1825), expresses the opin- ion that varieties change gradually into perma- nent species, which are no longer capable of intercrossing. In 1826 Prof. Grant of Edin- burgh published a paper on the spongilla in the "Philosophical Journal," in which he held that species are descended from other species, and that they become improved in the course of modification. Karl Ernst von Baer, in his Ueber Entwiclcelungsgeschichte der Thien (1828), maintains similar views as to animals, Oken, in his Naturphilosophie (1843), published his belief in the development of species ; anc in 1846 J. d'Omalius d'Halloy of Brussels ex- pressed his opinion that probability favors this theory rather than that of separate creations Isidore GeoiFroy Saint-Hilaire, in his lectures published in 1850, gives reasons for his belief ir the modification of species by circumstances, and in the transmission of differences thus produced. In 1852 Herbert Spencer arguec that species have undergone modificatior through change of circumstances. M. Nau din in the same year published a paper or the origin of species in the Revue horticole, ir which he averred his belief that botanica species are formed in a manner analogous tc varieties under cultivation ; and Franz linger also in 1852, expressed similar opinions in hi; Versuch einer Geschichte der Pflanzenwelt In 1853 Dr. Schaffhausen, in a paper publishec in the Verhandlungen des Naturhistorischej Vereins des preussischen Rheinlands, &c., main tained the doctrine of progressive developmenl of organic forms. On July 1, 1858, two essay* were read before the Linnaaan society, one bj Charles Robert Darwin, entitled U 0n the Tendency of Species to form Varieties, and or the Perpetuation of Species and Varieties bj