The fitness of any evolutionary unit can be understood in terms of its two basic components: fecundity (reproduction) and viability (survival). Trade-offs between these fitness components drive the evolution of life-history traits in extant multicellular organisms. We argue that these trade-offs gain special significance during the transition from unicellular to multicellular life. In particular, the evolution of germ–soma specialization and the emergence of individuality at the cell group (or organism) level are also consequences of trade-offs between the two basic fitness (...) components, or so we argue using a multilevel selection approach. During the origin of multicellularity, we study how the group trade-offs between viability and fecundity are initially determined by the cell level trade-offs, but as the transition proceeds, the fitness trade-offs at the group level depart from those at the cell level. We predict that these trade-offs begin with concave curvature in single-celled organisms but become increasingly convex as group size increases in multicellular organisms. We argue that the increasingly convex curvature of the trade-off function is driven by the cost of reproduction which increases as group size increases. We consider aspects of the biology of the volvocine green algae – which contain both unicellular and multicellular members – to illustrate the principles and conclusions discussed. (shrink)
This chapter combines formal models of how the fitness of a collective can become decoupled from the fitness with more empirical work on the volvocine algae. It uses the Volvox clade as a model system. It describes the evolution of altruism in the volvocine green algae. This chapter suggests that altruism may evolve from genes involved in life-history trade-offs. It shows the several cooperation, conflict, and conflict mediation cycles in the volvocine green algae. This cycle of cooperation, conflict, and conflict (...) mediation drives evolutionary transitions in individuality. (shrink)
Adaptations can occur at different hierarchical levels, but it can be difficult to identify the level of adaptation in specific cases. A major problem is that selection at a lower level can filter up, creating the illusion of selection at a higher level. We use optimality modeling of the volvocine algae to explore the emergence of genuine group adaptations. We find that it is helpful to develop an explicit model for what group fitness would be in the absence of group-level (...) relationships between traits and group fitness. We call this “counterfactual fitness,” because in many actual cases of interest there are group-level relationships. Once counterfactual fitness is modeled, the difference between effects that filter up and genuine group selection is explicit and so, therefore, is the distinction between apparent and genuine group adaptations. We call the latter group-specific adaptations. Recognizing group-specific adaptations is important because only group-specific adaptations would cause the lower-level units to be maladapted if they were to leave the group and enter a global cell-level population. Thus, as group-specific adaptations evolve, they create selective pressure for increased cohesiveness and individuality of groups. This article suggests that group-specific adaptations could be present in the simplest, earliest branching colonial volvocine species, which do not have distinct specialized cells. The article also makes predictions about the kind of empirical evidence needed to support or refute the hypothesis that a particular trait is a group-level adaptation. (shrink)
Understanding good design requires addressing the question of what units undergo natural selection, thereby becoming adapted. There is, therefore, a natural connection between the formal Darwinism project (which aims to connect population genetics with the evolution of design and fitness maximization) and levels of selection issues. We argue that the formal Darwinism project offers contradictory and confusing lines of thinking concerning level(s) of selection. The project favors multicellular organisms over both the lower (cell) and higher (social group) levels as the (...) level of adaptation. Grafen offers four reasons for giving such special status to multicellular organisms: (1) they lack appreciable within-organism cell selection, (2) they have multiple features that appear contrived for the same purpose, (3) they possess a set of phenotypes, and (4) they leave offspring according to their phenotypes. We discuss why these rationales are not compelling and suggest that a more even-handed approach, in which multicellular organisms are not assumed to have special status, would be desirable for a project that aims to make progress on the foundations of evolutionary theory. (shrink)
We review Evolution and the Levels of Selection by Samir Okasha. This important book provides a cohesive philosophical framework for understanding levels-of-selections problems in biology. Concerning evolutionary transitions, Okasha proposes that three stages characterize the shift from a lower level of selection to a higher one. We discuss the application of Okasha’s three-stage concept to the evolutionary transition from unicellularity to multicellularity in the volvocine green algae. Okasha’s concepts are a provocative step towards a more general understanding of the major (...) evolutionary transitions; however, the application of certain ideas to the volvocine model system is not straightforward. (shrink)
Recent philosophical discussions have failed to clarify the roles of the concept fitness in evolutionary theory. Neither the propensity interpretation of fitness nor the construal of fitness as a primitive theoretical term succeed in explicating the empirical content and explanatory power of the theory of natural selection. By appealing to the structure of simple mathematical models of natural selection, we separate out different contrasts which have tended to confuse discussions of fitness: the distinction between what fitness is defined as versus (...) what fitness is a function of, the contrast between adaptedness as an overall property of organisms and specific adaptive capacities, the distinction between actual and potential reproductive success, the role of chance versus systematic causal relations, fitness as applied to organisms as opposed to fitness applied to genotype classes, heritable adaptive capacities of genotypes as opposed to relations between genotypes and the environment. We show how failure to distinguish and properly interrelate these different aspects of “fitness” adds confusion to a number of already complex issues concerning evolutionary theory. On the basis of our discussion of these different aspects of “fitness”, we propose a terminology which makes the necessary distinctions. A central result of our analysis is that the concept of fitness as the overall adaptedness of organisms does not enter into the causal structure of evolutionary explanation, at least to the extent that this structure is represented in the mathematical models of natural selection. (shrink)
All disciplines must define their basic units and core processes. In evolutionary biology, the core process is natural selection and the basic unit of selection and adaptation is the individual. To operationalize the theory of natural selection we must count individuals, as they are the bearers of fitness. While canonical individuals have often been taken to be multicellular organisms, the hierarchy of life shows that new kinds of individuals have evolved. A variety of criteria have been used to define biological (...) individuality. Some criteria rely on the presence/absence of a particular property while others advocate an approach that reflects the process of natural selection. The plethora of approaches to classifying individuality has resulted in confusion regarding how to study individuality in a given taxon. (shrink)
Richard Wolin, in his article 'Nazism and the Complicities of Hans-Georg Gadamer: Untruth and Method' ( New Republic , 15 May 2000, pp. 36-45), wrongly accuses Gadamer of being 'in complicity' with the Nazis. The present article in reply was rejected by the New Republic , but is printed here to show that Wolin in his article is misinformed and unfair. First, Wolin makes elementary factual errors, such as stating that Gadamer was born in Breslau instead of Marburg. He (...) relies on a highly questionable source, Teresa Orozco, as 'definitive'. He argues often by misconstruing the evidence and guilt by association. For instance, he associates Gadamer with Werner Jaeger, with whom he disagreed and had little contact. Finally,he misinterprets basic terms in Gadamer's hermeneutics, Vorurteil and authority, attributing to them the popular sense of these terms instead of their place in Gadamer's hermeneutics. Vorurteil , popularly translated as 'prejudice', but better rendered as 'prejudgment', refers to the prior knowledge that one needs in order to understand a situation or a text. In some cases, this is part of the inherited tradition. Authority refers to the respect one pays to those one recognizes as having more knowledge than oneself: one's doctor, or parent, or teacher, a judge, or certain texts. It is not an abject surrender to all authority but the necessary respect for authority in human relationships and in society in general. By misconstruing these terms, Wolin attempts to discredit Gadamer's general philosophy,not just to demonstrate a connection to the Nazis. At the end, his argument turns into a misinformed general political attack on Gadamer as an enemy of Enlightenment values. (shrink)
Reviews evidence which suggests that there may be little or no direct introspective access to higher order cognitive processes. Ss are sometimes unaware of the existence of a stimulus that importantly influenced a response, unaware of the existence of the response, and unaware that the stimulus has affected the response. It is proposed that when people attempt to report on their cognitive processes, that is, on the processes mediating the effects of a stimulus on a response, they do not do (...) so on the basis of any true introspection. Instead, their reports are based on a priori, implicit causal theories, or judgments about the extent to which a particular stimulus is a plausible cause of a given response. This suggests that though people may not be able to observe directly their cognitive processes, they will sometimes be able to report accurately about them. Accurate reports will occur when influential stimuli are salient and are plausible causes of the responses they produce, and will not occur when stimuli are not salient or are not plausible causes. (shrink)
Disputes regarding the ethics of work by children have intensified in recent years, with little resolution. The impasses stem from failure to recognize the diverse forms of child work and a lack of empirical research regarding its causes and consequences. We report on data gathered in Brazil’s export-oriented shoe industry, which is notorious for the employment of children. Central findings are: 1) the causes of child work have less to do with backwardness and more to do with how shoe workers (...) are integrated into the global order; 2) local employers and children regard this work as benign, but the U.S. government sees it as hazardous to children and unfair to U.S. producers; 3) efforts to remove children from the shoe industry have been frustrated by local resistance and raise ethical questions; and 4) in certain circumstances, efforts to eliminate hazards from the workplace are morally superior to campaigns to remove childworkers from employment. (shrink)
The authors find East Asians to be holistic, attending to the entire field and assigning causality to it, making relatively little use of categories and formal logic, and relying on "dialectical" reasoning, whereas Westerners, are more analytic, paying attention primarily to the object and the categories to which it belongs and using rules, including formal logic, to understand its behavior. The 2 types of cognitive processes are embedded in different naive metaphysical systems and tacit epistemologies. The authors speculate that the (...) origin of these differences is traceable to markedly different social systems. The theory and the evidence presented call into question long-held assumptions about basic cognitive processes and even about the appropriateness of the process–content distinction. (shrink)
A few years ago I ran across a statement by Jean-Paul Sartre which seemed to imply that if there is a God, then there can be no human freedom. That thesis struck me as questionable, but at the time I did not pause to examine it. More recently I ran across a similar, more explicit statement by Kurt Baier, and I decided the time to pause had come. My knee-jerk response to Baier – and I confess it was probably nothing (...) more – was, ‘Why can't there be human freedom if there is a God? Indeed, can there be human freedom if there isn't a God ?’ The second of these questions has proved to be the more provocative to me, for the more I have thought about it, the more it has seemed to me that it is the atheist and not the theist who should be on the defensive about libertarianism, i.e. the position that human beings do act, that human actions are not determined, that we are the sole cause of our actions, and that all things remaining the same, we could have done otherwise. Indeed, the more I thought about that question – Can there be human freedom if there is no God? – the more convinced I became that the atheist has no good reason for believing in libertarianism. Note: I am not saying that atheism is logically incompatible with libertarianism. Perhaps it is, but if it is, that is not yet obvious to me. Rather, I am saying that an atheist who believes in libertarianism must believe in it on the basis of faith and must hold this faith in opposition to the only type of evidence that is available to him. Hence, by denying the existence of God, Baier and Sartre do not make room for human freedom; they make belief in human freedom irrational. By contrast, I shall argue, the theist does have a good reason for believing that humans are free. Let's take separate looks at Baier and Sartre; then I shall summarize the substance of my position. (shrink)
Staged 2 different videotaped interviews with the same individual—a college instructor who spoke English with a European accent. In one of the interviews the instructor was warm and friendly, in the other, cold and distant. 118 undergraduates were asked to evaluate the instructor. Ss who saw the warm instructor rated his appearance, mannerisms, and accent as appealing, whereas those who saw the cold instructor rated these attributes as irritating. Results indicate that global evaluations of a person can induce altered evaluations (...) of the person's attributes, even when there is sufficient information to allow for independent assessments of them. Furthermore, Ss were unaware of this influence of global evaluations on ratings of attributes. In fact, Ss who saw the cold instructor actually believed that the direction of influence was opposite to the true direction. They reported that their dislike of the instructor had no effect on their rating of his attributes but that their dislike of his attributes had lowered their global evaluations of him. (shrink)
While reflecting one day on the enormous difficulties that men have in knowing that there is a God, a completely unexpected and unfamiliar question drifted into my purview – perhaps as a kind of ultimate expression of my philosophical frustration. ‘Indeed’, the question asked, ‘can even God know that he is God?’ At first I thought this query merely amusing. ‘Wouldn't it be funny if God cannot know that he is God! But of course he can.’ So my mind wandered (...) on to other things. The question did not leave me alone, though. It insisted that I take it seriously, and the more I did, the more legitimate, complex, and significant it came to seem - and still does. (shrink)
Quine and others have recommended principles of charity which discourage judgments of irrationality. Such principles have been proposed to govern translation, psychology, and economics. After comparing principles of charity of different degrees of severity, we argue that the stronger principles are likely to block understanding of human behavior and impede progress toward improving it. We support a moderate principle of charity which leaves room for empirically justified judgments of irrationality.
When Kleene extended his recursive realizability interpretation from intuitionistic arithmetic to analysis, he was forced to use more than recursive functions to interpret sequences and conditional constructions. In fact, he used what classically appears to be the full continuum. We describe here a generalization to higher type of Kleene's realizability, one case of which, -realizability, uses general recursive functions throughout, both to realize theorems and to interpret choice sequences. -realizability validates a version of the bar theorem and the usual continuity (...) principles, while also providing naturally, as Kleene's 1965 realizability does not, for versions of lawless sequence axioms, as well as of Church's Thesis. (shrink)
SECRETS OF THE TEMPLE : HOW THE FEDERAL RESERVE RUNS THE COUNTRY by William Greider New York: Simon and Schuster, 1987. 798 pp., $24.95 Greider pursues the theme that the Federal Reserve System promotes the interests of Wall Street?banks and bondholders?over those of Main Street?the rest of society. The wealth of fascinating observations he makes are, unfortunately, organized by a 1950s?style Keynesianism and a faith in unlimited, majoritarian democracy. Neither of these beliefs are at all adequate for remedying the deficiencies (...) of political control of the money supply, which is the real problem Greider has uncovered. (shrink)
I want to state as clearly as I can the sense in which Kant is, and the sense in which he is not, a phenomenalist. And I also want to state the argument which Kant presents, in the Transcendental Deduction, for his particular version of phenomenalism. Since that doctrine has been stated by Kant himself as the view that we have knowledge of “appearances” only, and not of things in themselves, or that material objects are nothing but a species of (...) our “representations,” it will of course be part of my task in this paper to deal with these fundamental notions. Some recent works on Kant have completely misinterpreted these notions, and because of this they have failed to capture the peculiar character of Kant’s phenomenalism. Jonathan Bennett, for example, interprets Kant’s claim that “objects are nothing but representations” as the claim that “statements about objects must be translatable into statements about intuitions.” I shall call such a view a reductive phenomenalism and argue in this paper that Kant is not a reductive phenomenalist. But Kant is, all the same, a phenomenalist. I shall call him an existential phenomenalist. The difference is this: Kant does not maintain, as Bennett claims, that all propositions which assert or presuppose the existence of objects must be translatable into statements which refer to intuitions alone, but he does hold that all such propositions are translatable into statements about the existence of intuitions alone. When Kant tells us, therefore, that objects are mere “appearances,” he is not offering a theory about what empirical objects are or about what we are really referring to when we refer to such objects, but he is offering a theory about the sense in which any empirical objects can meaningfully be said to exist. The significance of the distinction between reductive and existential phenomenalism is great. For it both allows Kant to do justice to those considerations which appear to lead to idealism or phenomenalism, while it does not at the same time require him to deny that the level at which we speak of material bodies and states is, and must be, a basic level of our conceptual framework. It cannot be one which is itself built upon, or constructed out of, some more basic level, e.g., out of talk about sense-data or sensory states. The uniqueness of Kant’s phenomenalism lies precisely at this point. (shrink)
A long-standing challenge to evolutionary theory has been whether it can explain the origin of complex organismal features. We examined this issue using digital organisms—computer programs that self-replicate, mutate, compete and evolve. Populations of digital organisms often evolved the ability to perform complex logic functions requiring the coordinated execution of many genomic instructions. Complex functions evolved by building on simpler functions that had evolved earlier, provided that these were also selectively favoured. However, no particular intermediate stage was essential for evolving (...) complex functions. The first genotypes able to perform complex functions differed from their non-performing parents by only one or two mutations, but differed from the ancestor by many mutations that were also crucial to the new functions. In some cases, mutations that were deleterious when they appeared served as stepping-stones in the evolution of complex features. These findings show how complex functions can originate by random mutation and natural selection. (shrink)
H.P. Grice is known principally for his influential contributions to the philosophy of language, but his work also includes treatises on the philosophy of mind, ethics, and metaphysics--much of which is unpublished to date. This collection of original essays by such philosophers as Nancy Cartwright, Donald Davidson, Gilbert Harman, and P.F. Strawson demonstrates the unified and powerful character of Grice's thoughts on being, mind, meaning, and morals. An introductory essay by the editors provides the first overview of Grice's work.
In this article, the authors review a contemporary social psychological perspective on persuasion with an emphasis on explicating the psychological processes that underlie successful attitude change. Those mechanisms by which variables in the persuasion setting can influence attitude change are: affect the amount of information processing; bias the thoughts that are generated or one’s confidence in those thoughts ; serve as persuasive arguments or evidence or affect attitudes by serving as simple cues and heuristics. By grouping the persuasion processes into (...) meaningful categories, the authors aim to provide a useful guide to organize and facilitate access to key findings in this literature. They also describe a theoretical framework to understand the circumstances for which the different processes are more likely to influence our judgments, such as when variables precede or follow thought-generation, and when the extent of thinking is relatively low, medium, or high. (shrink)
This book examines two questions: Do people make use of abstract rules such as logical and statistical rules when making inferences in everyday life? Can such abstract rules be changed by training? Contrary to the spirit of reductionist theories from behaviorism to connectionism, there is ample evidence that people do make use of abstract rules of inference -- including rules of logic, statistics, causal deduction, and cost-benefit analysis. Such rules, moreover, are easily alterable by instruction as it occurs in classrooms (...) and in brief laboratory training sessions. The fact that purely formal training can alter them and that those taught in one content domain can "escape" to a quite different domain for which they are also highly applicable shows that the rules are highly abstract. The major implication for cognitive science is that people are capable of operating with abstract rules even for concrete, mundane tasks; therefore, any realistic model of human inferential capacity must reflect this fact. The major implication for education is that people can be far more broadly influenced by training than is generally supposed. At high levels of formality and abstraction, relatively brief training can alter the nature of problem-solving for an infinite number of content domains. (shrink)