"As a child I was passionately curious about everything, but especially about nature as seen in the plains and mountains of Colorado where I grew up. Nevertheless I entered college with the rather vague intention of becoming a writer, perhaps a poet. I was good at mathematics, but rejected a major in that subject because abstract mathematics is not about anything. In writing, too, I then saw that words are worth only what they convey, what they are about.

From an exceptional professor of geology I learned that even I could discover things wholly unknown before. I took to research compulsively, and research has governed my professional life ever since. The most vital aspect of geology is that which is literally vital, dealing with life: paleontology. The meaning of the fossil record and of the wonderful plants and animals around us can be understood only in an evolutionary context. Thus through the years I became more and more an evolutionary biologist, while also constantly investigating the nexus of this subject with geology. I have also continued to be a compulsive writer and this, as a rule, is what I have had to write about. What success I have had is mainly due to my publications, which contain mistakes, but which also have helped to initiate or orient some important trends in geology and biology." (23 February 1973, written for "Who's Who in America.")

[I] ceased to be a Christian at about 12....I became more and more critical and increasingly realized that practically nothing the preachers throw at you has any likelihood of being true (Autobiographical Notes, 1954, p. 17). I got over the effects of Presbyterian theology before I was far into my teens....While still in graduate school I had of course read "The Origin of Species"...[and was] already anti-vitalistic [and] a firm Neo- Darwinian....By the 1930s...I had reached a philosophical and theoretical viewpoint that seemed to have some originality and some importance.("Questionnaire" 1974, Amer. Phil. Soc. archives, Mayr Folder #3, p. 2,3,5,9. )

I had in childhood very strong feelings about nature, or about the world. I wanted to know things; even as a child too young to know this was impossible I wanted to know everything, not just nature in the narrow sense of the word. Religion I was exposed to, but could take it or leave it, and I did leave formal, dogmatic religion as soon as I decided there was nothing real to know about it....I was not concerned about the meaning of evolution "from the beginning"--beginning of what? When I learned, late teens, that evolution has occurred, of course I then wanted to puzzle at its meaning, if any....mainly an explanation and a significance for our lives...(Simpson to Laporte letter, 27 April 1981, Amer. Phil. So. archives).

Biology did interest me, and I began making up [at Yale] the serious gap on this of my knowledge requisite for paleontological work. ("Autobiographical Notes," 1933, American Philosophical Society archives.)

If I didn't fear I'd do you harm...I'd try to make you [Anne] an atheist. I really do think that you are a deluded follower of mistaken and superstitious & cowardly theories. That's as far as I'll go....Everyone who worships a god worships a force back of all nature, no matter what they call him or it and even if they call his aspects by different names & have many "gods." If there really is such a force, then all people who worship any god or gods, worship the same god. I'd just as soon call him Ishtar or Baal or Jehovah. They're merely names for the same idea. (Letter from Simpson to Anne Roe, written ca. 1920-21, when Anne was briefly flirting with fundamentalist Christianity, American Philosophical Society archives.)

Any sensitive person must feel a basically religious awe in the face of the mysteries of life and of the universe, but belief in an anthropomorphic god, in a savior, or in a prophet is nonsense. (Autobiographical Notes, 1970, p. 17.)

Very important to me was Kingsley's book, "Madam How and Lady Why." To that remarkable work I can trace very definitely and without doubt, not only my first understanding, however dim then, of the scientific method and, more distinctly but equally surely, the vague beginnings of a scientific philosophy. (1933 autobiographical notes, American Philosophical Society archives.) [Rev. Charles Kingsley (1819-1875) was an English cleric, poet, and novelist. His "Water Babies" and especially "Madam How and Lady Why" were written to encourage children to use their own eyes and reason to give understanding and meaning to the world around them, ultimately in order to recognize God, Who was behind it all.]

The conflict between science and religion has a single and simple cause. It is the designation as religiously canonical of any conception of the material world open to scientific investigation....As a matter of fact, most of the dogmatic religions have exhibited a perverse talent for taking the wrong side on the most important concepts of the material universe, from the structure of the solar system to the origin of man. The result has been constant turmoil for many centuries, and the turmoil will continue as long as religious canons prejudge scientific questions. ("This View of Life," 1964, p. 214.)

The greatest impact of the Darwinian revolution...was that it completed the liberation from superstition and fear that began in the physical sciences a few centuries before. Man, too, is a natural phenomenon. ("The evolutionary concept of man," 1972, p. 35.)

By early Victorian things belonged outside the realm of material principles and secular history....Perception of the truth of evolution was an enormous stride from superstition to the rational universe. [With] Darwin's theory...the essential point was the demonstration that material causes of evolution are possible and can be investigated scientifically. ("The world in which Darwin led us," 1961, p. 967, 969.)

For adaptation to evolve there must have been some kind of feedback between organism and environment....Darwin correctly placed the whole feedback in the population and discovered the basic mechanism [of natural selection]. That was his greatest accomplishment. ("The present status of the theory of evolution," 1969, p. 153.)

Among the things most characteristic of organisms--most distinctive of living as opposed to inorganic systems--is a sort of directedness. Their structures and activities have an adaptedness, an evident and vital usefulness to the organism. Darwin's answer and ours is to accept the common sense view...[that] the end ("telos") [is] that the individual and the species may survive. But this end is (usually) unconscious and impersonal. Naive teleology is controverted not by ignoring the obvious existence of such ends but by providing a naturalistic, materialistic explanation of the adaptive characteristics serving them. (Book review in "Science," 1959, p. 673.)

Over and over again in the study of the history of life it appears that what can happen does happen. There is little suggestion that what occurs must occur, that it was fated or that it follows some fixed plan, except simply as the expansion of life follows the opportunities that are presented. In this sense, an outstanding characteristic of evolution is its opportunism. [This is reminiscent of Dostoevsky saying, "If there is no God, everything is allowed."] ("Meaning of Evolution," 1949, p. 160.)

When different phyla [or lineages] acquire similar habiti [or ways of life] some time after their separation from a common ancestry, there is no inherent tendency for [subsequent] modifications to arise in the same way in the independent lines....There may be a form similar [structures], but there appears to be no fixed tendency for these to form in the same way or from the same parts in independent groups....Animals which fulfill this last condition are usually closely related...but I conceive the conditioning factor to be not the metaphysical one of germinal predestination [à la H.F. Osborn?] but the physical one of mechanical resemblance. ("A new Paleocene Uintathere and molar evolution in the Amblypoda," 1929, p. 7-8.)

[Darwin] gave an answer to the tremendous question that so deeply concerns...What is Man? [He] answered this question to the effect that man is a natural product of the universe; is an animal, a vertebrate, a mammal, and a primate....By bringing man into the evolutionary picture, Darwin finally took the last step in our emancipation and finally made our world rational. [Yet] Darwin felt humility and awe that seem to me truly religious. ("Darwin led us into this modern world," 1959, p. 271-272.)

Man is a glorious and unique species of animal. The species originated by evolution.... Future evolution could raise man to superb heights as yet hardly glimpsed, but it will not automatically do so. As far as can now be foreseen, evolutionary degeneration is at least as likely in our future as is further progress.The only way to ensure a progressive evolutionary future for mankind is for man himself to take a hand in the process. Although much further knowledge is needed, it is unquestionably possible for man to guide his own evolution (within limits) along desirable lines. But the great weight of the most widespread...beliefs and institutions is against even attempting such guidance. ("Man's evolutionary future," 1960, p. 134.)

When I read ["Genetics and the Origin of Species" by Dobzhansky in 1937] it opened a whole new vista to me of the possibilities of really explaining the things one could see going on in the fossil record and also the study of recent animals. I began pulling things together into this framework but also with a good many points that were not involved in the work of the geneticists, began thinking what my own, by this time rather long, studies of the history of life might mean within this context. ("Tapes," 1975, p. 45.)

I am keenly aware that much of Tempo & Mode now seems primitive and that parts of it have been invalidated. Nevertheless, ... its thesis has stood up well. That thesis, in briefest form, is that the history of life, as indicated by the available fossil record, is consistent with the evolutionary processes of genetic mutation and variation, guided toward adaptation of populations by natural selection, and furthermore that this approach can substantially enhance evolutionary theory, especially in such matters as rates of evolution, modes of adaptation, and histories of taxa, particularly at superspecific levels. ("The compleat paleontologist?," 1976, p. 5.)

The geneticists tended to consider that paleontology was incapable of rising above pure description and they did not even take the trouble to study descriptive paleontology for its bearing on genetics. It was easier to conclude that it had no such bearing. The paleontologists were, as a rule, quite willing to accept this stultifying conclusion, which also spared them the trouble of learning genetics. ("Tempo and Mode in Evolution," 1946, p. 53; the paper in the N.Y. Academy of Sciences Transactions, not the 1944 book of the same title.)

Now age thirty-five and more than ten years out of graduate school I dared to take modest personal steps in the direction of principles and theory. ("Concession to the Improbable," 1978, p. 81.)

The present purpose is to discuss the "how" and the "why" of evolution...not the"what" ...[the "how"] is more immediately interesting to the nonpaleontological evolutionist. ("Tempo and Mode in Evolution," 1944, p. xviii.)

A change was then [1939] in the air, especially as regards systematics which among all the ramifications of zoology necessarily remains its basic discipline....The population approach has now [1960] become usual in systematics and has spread into all branches of zoology. ("Quantitative Zoology," 2nd. ed., 1960, p. v.)

"I...repeat my conviction that the basic processes are the same at all levels of evolution, from local populations to phyla, although the circumstances leading to higher levels are special and the cumulative results of the basic processes are characteristically different at different levels." [Simpson expressing his view that macroevolution and microevolution partake of the same processes. For him, there is no hierarchical decoupling.] ("Nature and origin of supraspecific taxa," 1959, p. 255.)

Paleontology is characterized, but not fully defined, by having its own objective subject matter: fossils. Fossils occur in rocks, and they are organisms. Their extended study necessarily overlaps widely into both of the broader (or more miscellaneous) sciences of geology and biology. ("Some problems of vertebrate paleontology," 1961, p. 1679.)

I am trying to pursue a science that...has no name: the science of four-dimensional biology or of time and life. Fossils are pertinent...but Drosophila is equally pertinent. ("The Major Features of Evolution," 1953, p. xii.)

The history of organisms runs parallel with, is environmentally contained in, and continuously interacts with the physical history of the earth. ("Historical Science," 1963, p. 26.)

I have collected a great many fossils, described even more, and named a good number of them....Beyond that, I have taken a broader stance and a more theoretical and subjective one always in part in geology but increasingly also in organismal and evolutionary biology. ("Concession to the Improbable," 1978, p. 268.)

Paleontology associated with geology that paleontologists are often considered... perhaps as a rather odd kind of geologist. However, paleontologists are also biologists, and some of them...become quite as much concerned with biology as with geology. The particular aspects of biology that most occupy us are organismal and evolutionary: organismal because they deal with organisms as such...evolutionary because they deal with the course, causes, and principles of the evolution of whole organisms. The study of fossils is obviously relevant to those subjects, and when paleontology is combined with them the result is...appropriately designated as historical biology. ("Why and How," 1980, p. vii)

I have endeavored to develop or to follow an ideal of obtaining good central data and to relate this to the whole body of relevant use the new materials as a means and an occasion to renovate the whole structure. ("Autobiographical Notes," 1933, American Philosophical Society archives.)

It has never been entirely clear to me exactly what sort of paper you wanted, and I may have missed the point altogether. This is in any case an unusually labored effort and for some reason I have had great difficulty in selecting and organizing, from the embarrassingly vast amount of data at hand. [Simpson's doubts about one of his first "door-opener" papers dealing with more theoretical aspects of paleontology. See his 1936 article on super-specific variation that had been invited for an AAAS symposium that W. K. Gregory was organizing.] (Simpson to W. K. Gregory, 16 November 1936, Folder G, American Philosophical Society archives.)

The [statistical] figures certainly reveal no trend away from straight descriptive studies....Does this [lack of change] betoken desirable stability and maturity of research programs or does it indicate a lack of progress and undesirably narrow, routine, and unimaginative approaches to research? [Simpson compared the contents of the 1939 and 1949 volumes of the Journal of Paleontology and could find no significant impact of the evolutionary synthesis that had developed during the interval.] ("Journal of Paleontology," 1950, p. 499.)

Systematics is the scientific study of kinds and diversity of organisms and of any and all relationships among them, [whereas] taxonomy is the theoretical study of classification, including its bases, principles, procedures, and rules. ("Principles of Animal Taxonomy,"1961, p. 7, 11.)

The [Linnean] name, consequently, has remained merely a name, with little or no contained meaning or recognized significance. Such cases are unfortunately common in paleontology. At worst, they represent a sort of caveat, the author being unaware of what he has but wishing nevertheless to ensure credit for discovering it. At the best, in this case, the author [GGS] recognizes that he has something new which really requires a name, for the purposes of his enquiry, and he does the best he can to interpret it, even though that best cannot be very good. (Memoir Inst. Geol., Univ. Padua, vol. 9, p. 2, 1936.)

In the present state of [historical geology], an attempt to draw a conventional geographic map for any considerable part of the world during a remote geological epoch often involves quite as much fantasy as fact. For a world map, even the most fundamental points of geographic coordinates for crustal segments are still hotly disputed. Would it not be better to present to students...a consensus of actual knowledge and reasonable inference? (Book Review in "Science," 1960, p. 1885.)

[The maps in Dunbar's "Historical Geology"] represent in the main the last work of the late Charles Schuchert, acknowledged leader in this study. They ingeniously avoid appearance of knowledge where none exists by attractive use of clouds over marginal parts of the landscape. (Book review in "Natural History" magazine, 1949, p. 342.)

As all geologists know, the most important development in recent years bearing on paleogeography is the theory of plate tectonics and the consequent general acceptance of the reality of continental drift. This gives a new framework for the geographic aspects of earth history. It has been recognized ever since geology began to be studied...that tectonic events have changed geography throughout geological history in various ways....Plate tectonics adds another feature to these changes: the actual movements of whole continents or considerable parts of them. Biogeography, both neo- and paleo-, adds to and emends the results of tectonic paleo-geography. ("Earth history at the century mark of the USGS," 1979, p. 4210.)

I have a debt, a loyalty to the museum; the best place for me to do what I wanted to do. ("Concession to the Improbable," 1978, p. 129.)

Perhaps I may be excused a personal remark unusual in scientific publication. The years that I spent in the San Juan Basin with good companions, with heavy, productive physical labor, with mind-stretching problems, with exciting discoveries, with marvelous nature all around me, were among the happiest of the many happy years of my life. ("History of vertebrate paleontology in the San Juan Basin," in "Advances in San Juan Paleontology," edited by S. Lucas, K. Rigby,Jr., and B. Kues, Univ. New Mexico Press, 1981, p. 23.)

My monograph on the Kamarakotos was written in English but translated in Caracas and published in Spanish....Some of my best friends are anthropologists, and I have published quite a few other things in the field of anthropology, broadly defined, but anthropologists have not paid much attention to this one. I think the reason is that its contribution of new materials was almost all objective description without much theoretical, philosophical, or even methodological predilection such as is now, for better or worse, more in the mainstream of anthropological thought. ("Concession to the Improbable," 1978, p. 96.)