Spontaneous generation

“ But the question whether spontaneous generation be a fact or not does not depend upon theoretical con­si­de­ra­tions; our negative response is based, and is so far soundly based, on repeated failures to demonstrate its occurrence. ”

“ The old idea of spontaneous generation is now taken in many different senses. It is owing to this indistinctness of the idea, and its application to so many different hypotheses, that the problem is one of the most contentious and confused of the science of the day. ”

“ But, at all events, his work served to draw the attention of his successors to this subject, and, however vague his ideas about spontaneous generation in certain lower forms of life, he at least took a firm stand in favor of the theory of generation from the egg in most cases. ”

“ The popular belief in abiogenesis, or the so-called 'spontaneous' generation of the lower forms of life, which was accepted by all the philosophers of antiquity, held its ground down to the middle of the seventeenth century. Notwithstanding the frequent citation of the phrase, wrongfully attributed to Harvey, 'Omne vivum ex ovo,' that great physiologist believed in spontaneous generation as firmly as Aristotle did. ”

“ While admitting that generation, sexual or asexual, is the mode of reproduction found among animals possessed of complex structure, the partisans of spontaneous generation held, on the strength of their experiments, that certain very low organisms might be developed spontaneously, without specific germs, in infusions of organic substances. ”

“ Towards the end of the seventeenth century it occurred to one inquiring mind that a particular case of spontaneous generation, which had been accepted by everybody without hesitation, was capable of a less mysterious explanation. ”

“ In the question of spontaneous generation, or archigony, which we can now answer more definitely, it must be borne in mind that by this conception we understand generally the non-parental generation of an organic individual, the339 origin of an organism independent of a parental or producing organism. ”

“ This much-disputed question of "spontaneous generation" seems so obscure, because people have associated with the term a mass of very different, and often very absurd, ideas, and have attempted to solve the difficulty by the crudest experiments. The real doctrine of the spontaneous generation of life cannot possibly be refuted by experiments. ”

“ And yet eminent scientists take up the pen again and again in order to demonstrate the possibility of the "Generatio spontanea." In this they do not rely upon the safe methods of natural science, but they proceed on philosophical lines of argument. Life, they suggest, must once have had a beginning, and we are hence forced to believe that spontaneous generation, even if not realizable under actual conditions, must have once occurred. ”

“ The progress of research has reduced to naught all the facts that pointed toward spontaneous generation, and so we find ourselves duly forced to turn away from spontaneous generation and to regard the living substance as given, just as the physicist regards matter, and takes no further thought as to the question of its origin. ”

“ Lamarck also clearly affirms the fact of spontaneous generation. "I hope to prove," he says, "that nature possesses means and faculties for the production of all the forms which we so much admire. Rudimentary animals and plants have {162}been formed, and are still being formed to-day, by spontaneous generation." ”

“ Spontaneous Genera′tion of Life, the doctrine that life in some form is developed from non-living matter. The ancients believed that frogs and eels sprang from mud, that insects were generated in dew, that decaying meat bred maggots, that the appearance of other forms of life was to be accounted for by spontaneous generation from lifeless matter. ”

“ The belief in what is erroneously called spontaneous generation—that is to say, in the development of living matter out of mineral matter, apart from the agency of pre-existing living matter, as an ordinary occurrence at the present day—which is still held by some of us, was universally accepted as an obvious truth by them. ”

“ Every scientist who believes in this form of origin holds that if the exact conditions are repeated the result will occur once more. He may believe that no such repetition is possible, but he is confident that, if it could be, life would arise again from lifeless matter.
This process of life arising from matter that is not alive is known as Spontaneous Generation. ”

“ Thus, in a certain sense, it was with the first biophors, originating through spontaneous generation, that the whole of the organic world was determined, for their origin involved not only the physical constitution by which the variations of the organism were limited, but also the external conditions, with their changes up till now, to which organisms had to adapt themselves. ”

“ It may be that it is impossible for us to produce the conditions requisite to the origination of life; but we must speak modestly about the matter, and recollect that Science has put her foot upon the bottom round of the ladder. Truly he would be a bold man who would venture to predict where she will be fifty years hence.
There is another inquiry which bears indirectly upon this question, and upon which I must say a few words. You are all of you aware of the phenomena of what is called spontaneous generation. ”

“ Idioplasm as bearer of the inheritable determinants; (2) Spontaneous generation; (3) Causes of variation; (4) Determinants and visible characters, in which the origin and function of the determinants is presented; (5) Variety, race, "nutrition variety," heredity and variation; (6) Criticism of the Darwinian theory of natural selection, in which the author urges seven objections to that theory; (7) Laws of evolution of the plant kingdom; (8) Alternation of generations from the standpoint of phylogeny ”

“ Of the myriads of generations which such a process of development may have occupied, perhaps the first set moved with suctorial processes, while the second gradually adopted sedentary habits, and throughout the whole of the long series, each succeeding generation must have been almost exactly like its predecessor, and must always have consisted of individuals which possessed the characters of the species. ”

“ In all the changes of structure which regularly supervene during old age, we see the effects of deteriorated growth, and not of true development.
In the so-called process of alternate generation many individuals are generated asexually during very early or later stages of development. ”

“ These naturalists thereby designate a gradual bodily transformation appearing in the course of generations in correspondence with the new requirements of altered conditions of life or, in other words, the action of natural selection, and not the result of a suddenly and direct acting transforming cause exerted but once on a generation. ”

“ But during the act of asexual production or subsequently to it, they often advance in organisation, as we see in the many cases of "alternate generation." In thus speaking of alternate generation, I follow those naturalists who look at the process as essentially one of internal budding or of fissiparous generation. ”

“ On considering this subject one should have imagined at first view, that it might have been easier for nature to have supported her progeny for ever in health and life, than to have perpetually reproduced them by the wonderful and mysterious process of generation. ”

“ If the mere anxiety connected with an ill-healing wound inflicted on but one generation is sometimes found to have so impressed the germ-cells that they hand down its scars to offspring, how much more shall not anxieties that have directed action of all kinds from birth till death, not in one generation only but in a longer series of generations than the mind can realize to itself, modify, and indeed control, the organization of every species? ”

“ I say, we have successive forms of animal life adapted to successive conditions (so far, proving design) , and not derived in natural succession in the ordinary way of generation. But if no single fact in actual nature allows us to suppose that the new species and orders were produced successively in the natural way, how did they begin? I reply, by a way out of and above common known, material nature, and this way I call CREATION. Generation and creation are two distinct ideas, and must be described by two distinct words, unless we wish to introduce utter confusion of thought and language. ”

“ And yet that which in our inner consciousness is a blind, vehement impulse, appears in our outer consciousness in the form of the most complex living organism we know. Generation, then, is manifestly the point at which the real and the seeming intersect each other.
Birth and death—the inevitable lot of each and every one—would seem to affect the individual only, the race living on without change or decay. This, however, is but the appearance. In reality the individual and the race are one. ”

“ From generation to generation, this lessening of the parts consequent on functional decline has been inherited. And since the survival of individuals must always have been determined by more important structural traits, this trait can have neither been facilitated nor retarded by natural selection. ”

“ Instead, they bud—give birth, in fact—to smaller ones, which increase until they reach the size of the preceding generation. And like the children of man and animals, these younger generations grow on precisely as their progenitors! ”

“ Considered in the light of this hypothesis, generation appears as a fact of disaggregation, occurring in an organism in process of equilibration: as a fact of disaggregation, which ever renews the evolution of the species, and which retards its equilibrium by multiplying the conditions under which the species may, under the influence of the incident forces of the environment, undergo a more perfect elaboration, the result of which shall be a better adaptation of the organism to its surroundings. ”

“ But, if acquired characters are not transmitted, the new generation is, on the whole, not much better, not much worse, than its predecessors—so far as this supposed factor of change is concerned. Each generation makes a fresh start, as we see in the babies of our slums to-day. ”

“ And on the whole the former sort will live longer, bear more offspring, and reproduce themselves more abundantly than the latter, and so generation by generation the average of the species will change in the favourable direction. ”

“ Well,—but isn't the stature stunted, physical, as well as mental and moral, when life is forced to reproduce itself, generation after generation, among the unnatural conditions of slums and industrialism? ”

“ I must own that I have great difficulty in believing that any temporary condition of the parents can affect the offspring. If it last long enough to affect the health or structure of the parents, I can quite believe the offspring would be modified. But how mysterious a subject is that of generation! Although my hypothesis of pangenesis has been reviled on all sides, yet I must still look at generation under this point of view; and it makes me very averse to believe in an emotion having any effect on the offspring. ”

“ Besides, it is not only possible, but even probable, that both theories—that of heterogenetic generation and that of gradual development—may have to share with one another in the explanation of the origin of species; and even that, especially for the lowest species and for the beginnings of the main types, primitive generation also has its share in the establishment of the paternity. ”

“ All those cases which come under the designation of ‘alternation of generation,’ can obviously be referred to cyclical heredity, as will be explained further on. In the one case the successive generations deport themselves67 exactly in the same manner as do the successive stages of development of the individual in the other; and we may conclude therefrom (as has long been admitted on other grounds) that a generation is, in fact, nothing else than a stage of development in the life of a species. ”

“ Phyletic growth, or the evolution of the organic world ever into higher and more complex forms, or at least into forms of different structure, is, as I have said, merely the sum of the processes of growth of the ancestors—together with the result of external influences on the forms during their development and their existence. This additional modification which the individuals as such undergo is—together with the influence of crossing—the very cause of the constantly progressing evolution. ”

“ By a retrospect of the past he is justified in cherishing 287 the hope of a brighter future for his descendants; no obstacle appears in view to bar their journey along the upward path; the illimitable capacity of protoplasm for physiological elevation may triumph over the universal cycle of birth, maturity, and decay; and in humanity as it exists we may see the progenitors of an infinitely superior, perhaps of an immortal race, the ultimate expression and end of evolution and generation. ”

“ The innate ability is handed down from generation to generation, and, in so far as it contributes to success, is fostered and developed by selection; and the modifications of behaviour to which it leads, since the results of prior process in the parent persist as the basis and starting-point of subsequent process in the offspring may in a sense also be said to be handed down. ”

“ And further, since the offspring, while inheriting their parents' peculiarities, tend, to vary somewhat from them, there will, in the next generation, probably be some who have the peculiarity in a greater degree than their parents, and others who have it in a lesser degree, when, if the conditions remain the same, there will be such a new survival of the fit, and such a fresh elimination of the unfit, as will leave the survivors in the third generation with the peculiarity developed, in however slight a degree, more than it was developed in their grandparents ”