Persistent Assumption Research Articles

Birth‐Death Models for differential persistence

Birth‐death models can generate synthetic flow sequences that demonstrate differential persistence, i.e., sequences in which low flows show more persistence than high flows do. A simple phenomenological model helps justify the assumption of differential persistence. The use of a birth‐death model, together with a set of modeling precepts, shows that differential persistence is a phenomenon of considerable descriptive importance but at least in some planning situations does not carry corresponding prescriptive importance.

The American Trader's Image of China, 1785-1840

A PERSISTENT ASSUMPTION in American historiography dealing with Sino-American relations is the belief that Americans held Chinese civilization in high esteem during the early years of the China trade, roughly 1785-1840. Recently, Harold Isaacs, in an introduction to his study of contemporary American images of the Chinese, characterized this period as one of respect, followed by an age of contempt between 1840 and 1905.1 Given the treatment of Sino-American relations by American historians, it is difficult to imagine Isaacs coming to any other conclusion. The pioneer works on the subject by Kenneth Latourette and Tyler Dennett conceived of the period before 1840 as one during which China inspired something of awe and even of envy in the traders and missionaries in Canton, if not in Americans in general.2 This interpretation has been reiterated by George H. Danton and Foster Rhea Dulles and appears in many diplomatic histories of the United States.3 The first Anglo-Chinese conflict in 1840 dramatically destroyed the esteem enjoyed by the Middle Kingdom, according to Latourette:

The Negro in the Political Life of the United States

American political philosophy and institutions are rooted in the fertile soil of eighteenth century liberalism. The dominant influence in American thinking at the time of the Revolution was civil libertarianism. This promised much for the status of the individual in the society. The American Revolution, admittedly bourgeois in character, and more a secession than a revolution, revealed a high regard for the rights of property as well as for the rights of the individual. Of greatest significance to the Negro, however, is the fact that this revolt handed down to the American society a constitutional framework that has become a sacred tradition, which embraces fundamental concepts of human equality and human rights. It is within this conceptual milieu, inherited from the American Revolution, that the Negro has carried on his struggles for social, political and economic emancipation. These concepts have given a measure of realism to the Negro's persistent assumption that he is entitled to equal status in the society, that he too has rights that he must fight for, that an individual black citizen is due as full a measure of human dignity as a white one. The Constitution itself, of course, represents a compromise solution between those conflicting groups in the Convention which actually feared democracy as a hydra-headed monster, on the one hand, and those which sincerely subscribed to the principles of fundamental equalitarianism, on the other. The entire constitutional history of the nation has reflected this compromise in the quixotic tendency to sanctify its democratic creeds while stubbornly retaining its racial bigotries. Paradoxical as it may seem in the light of the historical record, however, the fact remains that the Constitution did lay the basis for the most broad ideological pattern of individual human equality, human liberty and human rights that the modern world has known. The goal set for this nation by the Founding Fathers is the attainment of political democracy. It is the people who are to count in this society. Government is to be theirs-of, by and for them-all of them. Perhaps the most serious obstacle to the realization of this ideal goal has been the frailty of those who make up the society: the apathy, prejudices, intolerance, greed, and ignorance of the citizenry. Yet, it is, in a sense, of the essence of democracy that this should be so. This is at once the promise and the hazard of the democratic way. As one author aptly puts it:

The Indices of Refraction of the Plagioclase Feldspars

A study of the accuracy of determining the composition of plagioclase feldspars by means of the available curves of indices of refraction demonstrates that consistent results are impossible. Two outstanding causes of this unfortunate situation seem to be: (I) inaccuracy of the old chemical analyses used as basis for the composition, and (2) the persistent assumption that the plagioclase feldspars consist of two and only two end members or minals. Accurate data are needed before satisfactory curves can be drawn. The curves should be without excessive undulatory deviation from smooth ones, very close to straight lines. The composition should be in weight percentage.