Great Throughts Treasury

"The meaning of evolution is that man is the result of a purposeless, and natural process that did not have us in mind."

"Man is the result of a purposeless and natural process that did not have him in mind."

"Most of the dogmatic religions have exhibited a perverse talent for taking the wrong side on the most important concepts in the material universe, from the structure of the solar system to the origin of man."

"Species evolve exactly as if they were adapting as best they could to a changing world, and not at all as if they were moving toward a set goal."

"Given ample time and rather simple circumstances not likely to be unique in the universe, there does seem to be considerable probability , perhaps even inevitability, in the progress from dissociated atoms to macromolecules. The further organization of those molecules into cellular life would seem, on the face of it, to have a far different, very much lower order of probability. It is not impossible, because we know it did happen at least once. "

"A telescope, a telephone, or a typewriter is a complex mechanism serving a particular function. Obviously, its manufacturer had a purpose in mind, and the machine was designed and built in order to serve that purpose. An eye, an ear, or a hand is also a complex mechanism serving a particular function. It, too, looks as if it had been made for a purpose. This appearance of purposefulness is pervading in nature, in the general structure of animals and plants, in the mechanisms of their various organs, and in the give and take of their relationships with each other. Accounting for this apparent purposefulness is a basic problem for any system of philosophy or of science. "

"Virtually all biochemists agree that life on earth arose spontaneously from nonliving matter and that it would almost inevitably arise on sufficiently similar young planets elsewhere. "

"A rill in a barnyard and the Grand Canyon represent, in the main, stages of valley erosion that began some millions of years apart."

"Almost all paleontologists recognize that the discovery of a complete transition is in any case unlikely."

"Every paleontologist knows that most new species, genera, and families, and that nearly all categories above the level of family appear in the record suddenly and are not led up to by known, gradual, completely continuous transitional sequences."

"Biology that is truly such, that is, a study of living things, inevitably and always has a historical factor, and the physical principles of repeatability, predictability, and parity of prediction and explanation do not apply to the historical aspects of biology."

"Darwin recognized the fact that paleontology then seemed to provide evidence against rather for evolution in general or the gradual origin of taxonomic categories in particular."

"Because intelligence is our own most distinctive feature, we may incline to ascribe superior intelligence to the basic primate plan or to the basic plan of the mammals in general, but this point requires some careful consideration. There is no question at all that most mammals of today are more intelligent than most reptiles of today. I am not going to try to define intelligence or to argue with those who deny thought or consciousness to any animal except man. It seems both common and scientific sense to admit that ability to learn, modification of action according to the situation, and other observable elements of behavior in animals reflect their degrees of intelligence and permit us, if only roughly, to compare these degrees. In spite of all difficulties and all the qualifications with which the expert (quite properly) hedges his conclusions, it also seems sensible to conclude that by and large an animal is likely to be more intelligent if it has a larger brain at a given body size and especially if its brain shows greater development of those areas and structures best developed in our own brains. After all, we know we are intelligent, even though we wish we were more so."

"He is a state of matter, a form of life, a sort of animal, and a species of the Order Primates, akin nearly or remotely to all of life and indeed to all that is material."

"Certainly paleontologists have found samples of an extremely small fraction, only, of the earth's extinct species, and even for groups that are most readily preserved and found as fossils they can never expect to find more than a fraction."

"Human judgment is notoriously fallible and perhaps seldom more so than in facile decisions that a character has no adaptive significance because we do not know the use of it."

"I do not think evolution is supremely important because it is my specialty. On the contrary, it is my specialty because I think it is supremely important."

"I have a debt, a loyalty to the museum; the best place for me to do what I wanted to do."

"I don't know where to put whales. I'm sticking them here, but I don't have any reason for it."

"Life arose as a living molecule or protogene, the progression from this stage to that of the ameba is at least as great as from ameba to man. All the essential problems of living organisms are already solved in the one-celled (or, as many now prefer to say, noncellular) protozoan and these are only elaborated in man or the other multicellular animals. The step from nonlife to life may not have been so complex, after all, and that from cell to multicellular organism is readily comprehensible. The change from protogene to protozoan was probably the most complex that has occurred in evolution, and it may well have taken as long as the change from protozoan to man."

"In summary, very large populations may differentiate rapidly, but their sustained evolution will be at moderate or slow rates and will be mainly adaptive. Populations of intermediate size provide the best conditions for sustained progressive and branching evolution, adaptive in its main lines, but accompanied by in-adaptive fluctuations, especially in characters of little selective importance. Small populations will be virtually incapable of differentiation or branching and will often be dominated by random in-adaptive trends and peculiarly liable to extinction, but will be capable of the most rapid evolution as long as this is not cut short by extinction."

"Life is the most important thing about the world, the most important thing about life is evolution. Thus, by consciously seeking what is most meaningful, I moved from poetry to mineralogy to paleontology to evolution."

"In spite of these examples, it remains true, as every paleontologist knows, that most new species, genera, and families and that nearly all new categories above the level of families appear in the record suddenly and are not led up to by known, gradual, completely continuous transitional sequences."

"Man has risen, not fallen. He can choose to develop his capacities as the highest animal and to try to rise still farther, or he can choose otherwise. The choice is his responsibility, and his alone. There is no automatism that will carry him upward without choice or effort and there is no trend solely in the right direction. Evolution has no purpose; man must supply this for himself. The means to gaining right ends involve both organic evolution and human evolution, but human choice as to what are the right ends must be based on human evolution."

"Nothing I learned [in high school] had any bearing at all on the big and real questions. Who am I? What am I doing here? What is the world? What is my relationship to it?"

"It is still false to conclude that man is nothing but the highest animal, or the most progressive product of organic evolution. He is also a fundamentally new sort of animal and one in which, although organic evolution continues on its way, a fundamentally new sort of evolution has also appeared. The basis of this new sort of evolution is a new sort of heredity, the inheritance of learning. This sort of heredity appears modestly in other mammals and even lower in the animal kingdom, but in man it has incomparably fuller development and it combines with man's other characteristics unique in degree with a result that cannot be considered unique only in degree but must also be considered unique in kind. The Meaning of Evolution: A Study of the History of Life and of its Significance for Man (1949), 286."

"Now we do have many examples of transitional sequences."

"Of course the orders all converge backward in time, to different degrees."

"Scientists and particularly the professional students of evolution are often accused of a bias toward mechanism or materialism, even though believers in vitalism and in finalism are not lacking among them. Such bias as may exist is inherent in the method of science. The most successful scientific investigation has generally involved treating phenomena as if they were purely materialistic, rejecting any metaphysical hypothesis as long as a physical hypothesis seems possible. The method works. The restriction is necessary because science is confined to physical means of investigation and so it would stultify its own efforts to postulate that its subject is not physical and so not susceptible to its methods."

"Organisms, of course, have various characteristics in common, in degrees varying from such minimal resemblance as between, say, a man and a sequoia to the maximal resemblance of identical twins. Nevertheless, no two organisms, not even identical twins, are exactly alike. Each is the product of a history both individual and racial, and each history is different from any other, both unique and inherently unrepeatable. These aspects of biology deal not with the immanent, the inherent and changeless characteristics of the universe, but with contingency, its states, fleeting and in ceaseless change, each derived from everything that went before and conditioning everything that will follow. The possibilities of prediction are loose and limited, in principle because contingent states are unique and never exactly repeated, and even more so in practice because the historical antecedents are enormously complex and practically unknowable in complete detail. These facts also rule out the parity of prediction and explanation. Part of the explanation of what an organism is obliviously depends on what its ancestors were, what chances have occurred, and why and how. This is explanation after the fact, a posteriori, or by what has been called postdiciton. It is quite different from prediction, and the possibilities of prediction in an evolutionary sequence are decidedly limited. Thus principles firmly advanced as applicable to the philosophy of science in general are not in fact applicable to some of the most important aspects o biology. In this crisis surely it is obvious that the solution is not to restrict the scope of biology, practically excluding its most characteristic and most important aspects, but to broaden the scope of scientific principle and philosophy."

"Splitting and gradual divergence of genera is exemplified very well and in a large variety of organisms."

"Recognition of this kinship with the rest of the universe is necessary for understanding him, but his essential nature is defined by qualities found nowhere else, not by those he has in common with apes, fishes, trees, fire, or anything other than himself."

"The book before you is one of the most important ever written. No other modern work has done so much to change man’s concept of himself and of the universe in which he lives. Before Darwin the physical sciences were already well established. They had abandoned the magical and the supernatural in seeking to understand the operations of the physical universe. They had developed the basic principles of all truly scientific investigation: that natural causes should be sought for natural phenomena, and that scientific theories must be testable and tested, in terms of objective, repeatable observations. However, the most important of all phenomena, those of life, were not yet generally approached in that fully scientific wary. The usual attempts to explain the nature of life, the diversity of living things, their marvelous adaptations, and other fundamental aspects of the living world were still metaphysical, at best, and often frankly supernatural."

"The attempted synthesis of paleontology and genetics, an essential part of the present study, may be particularly surprising and possibly hazardous. Not long ago, paleontologists felt that a geneticist was a person who shut himself in a room, pulled down the shades, watched small flies disporting themselves in milk bottles, and thought that he was studying nature. A pursuit so removed from the realities of life, they said, had no significance for the true biologist. On the other hand, the geneticists said that paleontology had no further contributions to make to biology, that its only point had been the completed demonstration of the truth of evolution, and that it was a subject too purely descriptive to merit the name 'science'. The paleontologist, they believed, is like a man who undertakes to study the principles of the internal combustion engine by standing on a street corner and watching the motor cars whiz by."

"The meaning of human life and the destiny of man cannot be separable from the meaning and destiny of life in general. 'What is man?' is a special case of 'What is life?' Probably the human species is not intelligent enough to answer either question fully, but even such glimmerings as are within our powers must be precious to us. The extent to which we can hope to understand ourselves and to plan our future depends in some measure on our ability to read the riddles of the past. The present, for all its awesome importance to us who chance to dwell in it, is only a random point in the long flow of time. Terrestrial life is one and continuous in space and time. Any true comprehension of it requires the attempt to view it whole and not in the artificial limits of any one place or epoch. The processes of life can be adequately displayed only in the course of life throughout the long ages of its existence."

"The fact - not theory - that evolution has occurred and the Darwinian theory as to how it occurred have become so confused in popular opinion that the distinction must be stressed."

"The origin of life was necessarily the beginning of organic evolution and it is among the greatest of all evolutionary problems."

"The meaning that we are seeking in evolution is its meaning to us, to man. The ethics of evolution must be human ethics. It is one of the many unique qualities of man, the new sort of animal, that he is the only ethical animal. The ethical need and its fulfillment are also products of evolution, but they have been produced in man alone."

"The science of systematics has long been affected by profound philosophical preconceptions, which have been all the more influential for being usually covert, even subconscious."

"The passion for naming things is an odd human trait. It is strange that men always feel so much more at ease when they have put appellations on the things around them and that a wild, new region almost seems familiar and subdued once enough names have been used on it, even though in fact it is not changed in the slightest. Or, on second thought, it is perhaps not really strange. The urge to name must be as old as the human race, as old as speech which is one of the really fundamental characteristics by which we rise above the brutes, and thus a basic and essential part of the human spirit or soul. The naming fallacy is common enough even in science. Many a scientist claims to have explained some phenomenon when in truth all he has done is to give it a name."

"This regular absence of transitional forms is not confined to mammals, but is an almost universal phenomenon, as has long been noted by paleontologists. It is true of almost all orders of all classes of animals, both vertebrate and invertebrate. A fortiori, it is also true of the classes, and of the major animal phyla, and it is apparently also true of analogous categories of plants."

"The search for historical laws is, I maintain, mistaken in principle."

"The theory here developed is that mega-evolution normally occurs among small populations that become pre-adaptive and evolve continuously (without saltation, but at exceptionally rapid rates) to radically different ecological positions. The typical pattern involved is probably this: A large population is fragmented into numerous small isolated lines of descent. Within these, in-adaptive differentiation and random fixation of mutations occur. Among many such in-adaptive lines one or a few are pre-adaptive, i.e., some of their characters tend to fit them for available ecological stations quite different from those occupied by their immediate ancestors. Such groups are subjected to strong selection pressure and evolve rapidly in the further direction of adaptation to the new status. The very few lines that successfully achieve this perfected adaptation then become abundant and expand widely, at the same time becoming differentiated and specialized on lower levels within the broad new ecological zone."

"To put it crudely but graphically, the monkey who did not have a realistic perception of the tree branch he jumped for was soon a dead monkey—and therefore did not become one of our ancestors."