Academic social networks and social media have revolutionised the way individuals gather information and express themselves, particularly in academia, science, and research. Through the lens of academics, this study aims to investigate the epistemological and psychosocial aspects of these knowledge sources. The epistemological attitude model presented a framework to delve into and reflect upon the existence of knowledge sources, comprising subjective, interactional, and knowledge dimensions. One hundred and twenty-six university academics participated in this study, including lecturers and researchers from different (...) higher education institutions in Latvia. The study employed two methods: the Epistemological Attitudes towards Sources of Knowledge Questionnaire and the Epistemological Attitudes towards Sources of Knowledge Semantic Questionnaire. The data analysis involved several procedures, including exploratory and confirmatory factor analysis, correlation analysis, and test statistics. By implementing these methods, the study gained valuable insights into the sources of knowledge, examining them from two perspectives. The first perspective brought attention to the differences in academics’ appraisals by discussing their understanding, approach, use, and valuations of these sources. By scrutinising the constructs of meanings, the second perspective sheds light on the anticipated knowledge which is deemed ideal, the concrete knowledge that is both social and objective, and the subjectively valuable nature of academic social networks and social media. The findings underscore the specialised knowledge and qualities that academics rely on for producing knowledge. In terms of epistemology, methodology, social science, and education, the study holds theoretical and practical implications, especially in comprehending knowledge and its sources. (shrink)

I discuss the relevance of the current predicament in cosmology to the debate over scientific realism. I argue that the existence of two, empirically successful but ontologically inconsistent cosmological theories presents difficulties for the realist position.

The present PhD dissertation aims to examine the relation between modality and change in Aristotle’s metaphysics. -/- On the one hand, Aristotle supports his modal realism (i.e., worldly objects have modal properties - potentialities and essences - that ground the ascriptions of possibility and necessity) by arguing that the rejection of modal realism makes change inexplicable, or, worse, banishes it from the realm of reality. On the other hand, the Stagirite analyses processes by means of modal notions (‘change is the (...) actuality of what is virtual insofar as it is virtual’). In other words: to grasp what change is, one has to resort to the modal idiom of potentialities, while the fact that there is change is indicative of the fact that nature is full of modal properties. -/- Aristotle’s modal and kinetic realism finds a negative in the figure of the Megaric Diodorus Kronus. The polemical situation of Greek philosophy has indeed the dialectical advantage of not opposing the Aristotelian position to a sui generis straw man. Both in its reduction of modal judgements to temporal quantifications and in its dissolution of the reality of the state-of-being-in-motion in favour of a cinematographic view of processes, the philosophical figure of reductionist antirealism embodied by Diodorus constitutes an alternative that takes the opposite view of Aristotle’s realism. -/- The present study is structured as a discussion between these two positions. In the face of Diodorus’ antirealist challenges, Aristotle articulates modal and kinetic considerations: the answers he gives to Diodorus’ puzzles thus provide valuable insight into his metaphysics. Moreover, the examination of Aristotle’s and Diodorus’ metaphysics, because of their insight and originality, will not fail to interest the philosopher concerned with the metaphysical foundations of modern physics, insofar as the entanglement between modalities and processes is nowadays at the core of mechanics (phase spaces, path integrals, etc.). (shrink)

O objetivo deste artigo é discutir três problemas centrais na filosofia de David Hume. O primeiro é o do papel da associação de idéias: no Tratado há dois conceitos distintos dessa associação, falha corrigida na primeira Investigação, em que é eliminado o conceito de “associação costumeira” e não se atribui à associação qualquer papel na formação de inferências causais. O segundo diz respeito ao verdadeiro papel da indução. A filosofia humeana trata da descoberta dos poderes causais dos objetos, sem nunca (...) se ocupar de generalizações acerca de qualidades sensíveis. Hume descobriu o problema da “indução causal”, mas apenas como conseqüência de sua análise da inferência causal. O último de nossos problemas é o do exato conceito humeano daquele instinto que ele chama de “costume ou hábito”. O princípio de Hume mostra ser apenas uma sensibilidade à repetição de conjunções, sendo relevante apenas o elemento “repetição”, sem haver qualquer influência significativa da passagem do tempo, o que impede a interpretação desse princípio como “habituação” ou algo equivalente. Hume: three majors problemsThis article aims to discuss three central problems in David Hume’s philosophy. A first central problem in Hume’s philosophy concerns the role of the association of ideas: there are in the Treatise two distinct concepts of this association, a negligence that was corrected in the first Enquiry, where the concept of “customary association” is eliminated and no role is assigned to association in the formation of causal beliefs. The second is about the real meaning of induction. Hume’s philosophy discusses the discovery of the causal powers of objects, setting aside any generalisation about sensible qualities. Hume did discover the problem of “causal induction”, but only as a consequence of his analysis of causal inference. The last of our three problems concerns the exact Humean concept of the instinct he calls “custom or habit”. It is noticeable that Hume´s principle is just sensitiveness to the repetition of conjunctions, with no meaningful influence of the passage of time, and this goes against any interpretation of this principle as “becoming accustomed” or anything of the kind. (shrink)

Risk is an intrinsic part of our lives. In the future, the development and growth of the Internet of things allows getting a huge amount of data. Considering this evolution, our research focuses on developing a novel concept, namely Holistic Risk Assessment (HRA), that takes into consideration elements outside the direct influence of the individual to provide a highly personalized risk assessment. The HRA implies developing a methodology and a model. This paper is related to the epistemological positioning of this (...) research. We consider this research as an artificial science under the constructivism paradigm. We also introduce the positioning of this research in the complexity science paradigm. We end this paper by presenting a methodology based on an adapted Design Thinking Model. (shrink)

The problem of demarcating between what is scientific and what is pseudoscientific or merely unscientific - in other words, the problem of defining scientificity - remains open. The modern debate was firstly structured around Karl Popper's falsificationist epistemology from the 1930's, before diversifying a few decades later. His central idea is that what makes something scientific is not so much how adequate it is with data, but rather to what extent it might not have been so. Since the second half (...) of the century, and in the wake of criticisms, such as the Duhem-Quine thesis, that were raised against falsificationism(s), most approaches to the problem of scientific demarcation are now multicriteria and holistic. However, the approach presented in this paper does not follow the same guideline. The present work can be seen as an attempt to adapt Popper's (sophisticated) falsificationism to a model-based view of scientific knowledge. Using formalization and focusing on a particular epistemic unit of analysis (namely, empirical models) allows to properly define the popperian corroboration degree and to view scientificity as the maximization of this degree of corroboration over all available models and data. We eventually recover, in a natural way, well-accepted scientificity criteria: empirical adequacy, Lakatos' progressive problemshifts, balance between strength and simplicity, parsimony, and coherence as special cases of this general scientificity principle. From this viewpoint, the language dependency of our empirical knowledge no longer appears as a limitation of falsificationism but as one more reason to take it as a good epistemological framework. (shrink)

Contemporary theories of consciousness are based on widely different concepts of its nature, most or all of which probably embody aspects of the truth about it. Starting with a concept of consciousness indicated by the phrase “the feeling of what happens” (the title of a book by Antonio Damásio), we attempt to build a framework capable of supporting and resolving divergent views. We picture consciousness in terms of Reality experiencing itself from the perspective of cognitive agents. Each conscious experience is (...) regarded as composed of momentary feeling events that are combined by recognition and evaluation into extended conscious episodes that bind cognitive contents with a wide range of apparent durations (0.1 secs to 2 or more secs, for us humans, depending on circumstances and context). Three necessary conditions for the existence of consciousness are identified: a) a ground of Reality, envisaged as an universal field of potentiality encompassing all possible manifestations, whether material or 'mental'; b) a transitional zone, leading to; c) a manifest world with its fundamental divisions into material, 'informational' and quale-endowed aspects. We explore ideas about the nature of these necessary conditions, how they may relate to one another and whether our suggestions have empirical implications. (shrink)

Hume thought that if you believed in powers, you believed in necessary connections in nature. He was then able to argue that there were none such because anything could follow anything else. But Hume wrong-footed his opponents. A power does not necessitate its manifestations: rather, it disposes towards them in a way that is less than necessary but more than purely contingent. -/- In this paper a dispositional theory of causation is offered. Causes dispose towards their effects and often produce (...) them. But a set of causes, even though they may succeed in producing an effect, cannot necessitate it since the effect could have been counteracted by some additional power. This would require a separation of our concepts of causal production and causal necessitation. The most conspicuous cases of causation are those where powers accumulate and pass a requisite threshold for an effect to occur. -/- We develop a model for representing powers as constituent vectors within an n-dimensional quality space, where composition of causes appears as vector addition. Even our resultant vector, however, has to be understood as having dispositional force only. This model throws new light on causal modality and cases of prevention, causation by absence and probabilistic causation. (shrink)

Although the main focus of Hume’s career was in the humanities, his work also has an observable role in the historical development of natural sciences after his time. To show this, I shall center on the relation between Hume and two major figures in the history of the natural sciences: Charles Darwin (1809–1882) and Albert Einstein (1879–1955). Both of these scientists read Hume. They also found parts of Hume’s work useful to their sciences. Inquiring into the relations between Hume and (...) the two scientists shows that his philosophical positions had a partial but constructive role in the formation of modern biology and physics. This is accordingly a clear indication of Hume’s impact on the scientific tradition. Before proceeding to analyze Hume’s contribution to the history of science, it is important to address his broader role in the history of philosophy of science. Hume’s discussions concerning the topics of causation, induction, the distinction between mathematical and empirical propositions, and laws of nature have been important for the philosophy of science of the nineteenth and twentieth centuries. (shrink)

The first translation into Ukrainian and French of the article "Saber comum e ceticismo” (Common knowledge and skepticism) by Osvaldo Porchat Pereira (1933–2017), which became one of the classic sources of modern Brazilian Neopyrrhonism.

To be human is to imitate. This is a strong claim, and a contentious one. It implies that the turning point in hominid evolution was when our ancestors first began to copy each other’s sounds and actions, and that this new ability was responsible for transforming an ordinary ape into one with a big brain, language, a curious penchant for music and art, and complex cumulative culture. The argument, briefly, is this. All evolutionary processes depend on information being copied with (...) variation and selection. Most living things on earth are the product of evolution based on the copying, varying and selection of genes. However, once humans began to imitate they provided a new kind of copying and so let loose an evolutionary process based on the copying, varying and selection of memes. This new evolutionary system co-evolved with the old to turn us into more than gene machines. We, alone on this planet, are also meme machines. We are selective imitation devices in an evolutionary arms race with a new replicator. This is why we are so different from other creatures; this is why we alone have big brains, language and complex culture. There are many contentious issues here; the nature and status of memes, the validity of the concept of a replicator, the difference between this and other theories of gene-culture co-evolution, and whether memetics really is necessary, as I believe it is, to explain human nature. I shall outline the basic principles of memetics, show how memes could have driven human evolution, and consider some of these questions along the way. (shrink)

Radboud Universiteit Nijmegen, 06 september 2010.

Beginning by offering a conceptual analysis of change – a statement of what change of any kind is – the paper sets out to examine possible ways of understanding a very common and important variety of change that may be called ‘evolutionary’. These changes include anything from the production of a clay pot on a potter's wheel to the emergence of a system of management, or from the effects of an analgesic drug to the development of a new programme of (...) care. As few philosophers have discussed such topics, theories are borrowed from the philosophy of science that attempt to explain the development and rationality of science. The ideas of Karl Popper and Thomas Kuhn are discussed and criticized, before turning to evolutionary theories: Darwinian and Lamarckian. The paper ends by offering a model that, it is hoped, may help in thinking about a wide range of changes. (shrink)

Research on the nature of science and science education enjoys a longhistory, with its origins in Ernst Mach's work in the late nineteenthcentury and John Dewey's at the beginning of the twentieth century.As early as 1909 the Central Association for Science and MathematicsTeachers published an article – ‘A Consideration of the Principles thatShould Determine the Courses in Biology in Secondary Schools’ – inSchool Science and Mathematics that reflected foundational concernsabout science and how school curricula should be informed by them. Sincethen (...) a large body of literature has developed related to the teaching andlearning about nature of science – see, for example, the Lederman and Meichtry reviews cited below. As well there has been intensephilosophical, historical and philosophical debate about the nature of scienceitself, culminating in the much-publicised ‘Science Wars’ of recent time. Thereferences listed here primarily focus on the empirical research related to thenature of science as an educational goal; along with a few influential philosophicalworks by such authors as Kuhn, Popper, Laudan, Lakatos, and others. Whilenot exhaustive, the list should prove useful to educators, and scholars in otherfields, interested in the nature of science and how its understanding can berealised as a goal of science instruction. The authors welcome correspondenceregarding omissions from the list, and on-going additions that can be made to it. (shrink)

In this paper, I argue that Conway and Kochen’s Free Will Theorem (1,2) to the conclusion that quantum mechanics and relativity entail freedom for the particles, does not change the situation in favor of a libertarian position as they would like. In fact, the theorem more or less implicitly assumes that people are free, and thus it begs the question. Moreover, it does not prove neither that if people are free, so are particles, nor that the property people possess when (...) they are said to be free is the same as the one particles possess when they are claimed to be free. I then analyze the Free State Theorem (2), which generalizes the Free Will Theorem without the assumption that people are free, and I show that it does not prove anything about free will, since the notion of freedom for particles is either inconsistent, or it does not concern our common understanding of freedom. In both cases, the Free Will Theorem and the Free State Theorem do not provide any enlightenment on the constraints physics can pose on free will. (shrink)

SummaryTake the following version of scientific realism: we have good reason to believe that (some of the) current scientific theories tell us something specific about the underlying, i.e. unobservable, structures of the world, for instance that there are electrons with a certain electric charge, or that there are viruses that cause certain diseases. Popper, the rationalist, would not have adhered to the proposed formulation of scientific realism in terms of the rationality of existential beliefs concerning unobservables. Popper did not believe (...) in belief. According to Van Fraassen, the empiricist, one may yet have a rational existential belief concerning unobservables, given a liberal notion of rationality of belief. In this paper I will investigate to what extent a reassessment of both Popper’s rejection of the rationality of belief and Van Fraassen’s reformulation of the rationality of belief, points towards a new and pragmatist dissolution of the ‘problem of scientific realism’. (shrink)

Scientists are constantly making observations, carrying out experiments, and analyzing empirical data. Meanwhile, scientific theories are routinely being adopted, revised, discarded, and replaced. But when are such changes to the content of science improvements on what came before? This is the question of scientific progress. One answer is that progress occurs when scientific theories ‘get closer to the truth’, i.e. increase their degree of truthlikeness. A second answer is that progress consists in increasing theories’ effectiveness for solving scientific problems. A (...) third answer is that progress occurs when the stock of scientific knowledge accumulates. A fourth and final answer is that scientific progress consists in increasing scientific understanding, i.e. the capacity to correctly explain and reliably predict relevant phenomena. This paper compares and contrasts these four accounts of scientific progress, considers some of the most prominent arguments for and against each account, and briefly explores connections to different forms of scientific realism. (shrink)

After a brief comparison of Aliseda’s account with different approaches to abductive reasoning, I try to relate abduction, understood in terms like those of Aliseda, to another concept which also occupies a very important role in scientific change: idealization. In particular, I try to reveal some interesting aspects related to notions like approximation and empirical progress.

The ArgumentTwo dominant models of criticism are identified and analyzed. One is selfconsciously normative. It conceives of criticism as subject to strict logical rules. The other views itself as essentially descriptive and accounts for the critical activity in terms of social factors. In spite of their different origins and purposes, it is argued that both models share a reductionistic thrust, which minimizes the role of the critic qua agent. It is further agreed that neither provides an adequate account of critical (...) activity and its role in science. (shrink)

Common philosophical accounts of creativity align creative products and processes with a particular kind of agency: namely, that deserving of praise or blame. Considering evolutionary examples, we explore two ways of denying that creativity requires forms of agency. First, we argue that decoupling creativity from praiseworthiness comes at little cost: accepting that evolutionary processes are non-agential, they nonetheless exhibit many of the same characteristics and value associated with creativity. Second, we develop a ‘product-first’ account of creativity by which a process (...) is creative just in case it gives rise to products deserving of certain forms of aesthetic engagement. (shrink)

Donald T. Campbell outlines an epistemological theory that attempts to be faithful to evolution through natural selection. He takes his position to be consistent with that of Karl R. Popper, whom he credits as the primary advocate of his day for natural selection epistemology. Campbell writes that neither he nor Popper want to give up the goal of objectivity or objective truth, in spite of their evolutionary epistemology. In discussing the conflict between an epistemology based on natural selection and objective (...) truth, Campbell cites an article by the German sociologist and philosopher Georg Simmel entitled 'On a Connection of Selection Theory to Epistemology', as presenting the issue in a notably forthright manner.The present essay summarizes Simmel's article, with the purpose of clarifying, in terms that Campbell apparently finds satisfactory, the conflict that Campbell acknowledges between an evolutionary epistemology and ultimate truth; the essay then examines the responses of Campbell and Popper to Simmel's position. While Campbell and Popper acknowledge the work of Simmel, their responses suggest something less than a full consideration of Simmel's position. (shrink)

I offer an examination of trust relations in scientific inquiry as they seem to contrast with a lack of trust in an example of knowledge imposed from above by an unaccountable institutional power structure. On this basis I argue for a re-reading of John Hardwig's account of the place of trust in knowledge, and suggest that it translates less well than social epistemologists and others have assumed into a model for democratic epistemic practice.

Reichenbach held that all scientific inference reduces, via probability calculus, to induction, and he held that induction can be justified. He sees scientific knowledge in a practical context and insists that any rational assessment of actions requires a justification of induction. Gaps remain in his justifying argument; for we can not hope to prove that induction will succeed if success is possible. However, there are good prospects for completing a justification of essentially the kind he sought by showing that while (...) induction may succeed, no alternative is a rational way of trying.Reichenbach's claim that probability calculus, especially via Bayes' Theorem, can help to exhibit the structure of inference to theories is a valuable insight. However, his thesis that the weighting of all hypotheses rests only on frequency data is too restrictive, especially given his scientific realism. Other empirical factors are relevant. Any satisfactory account of scientific inference must be deeply indebted to Reichenbach's foundation work. (shrink)

Popper’s theory of learning is sometimes met with incredulity because Popper claims that there is no transference of knowledge or knowledge elements from outside the individual, neither from the physical environment nor from others. Instead, he claims that we can improve our present theories by discovering their inadequacies.The intent of this article is not to persuade educators to adopt Popper’s approach uncritically to build their professional knowledge. Rather, it presents a discussion on the need for teachers to adopt a critical (...) approach in eliminating what is inadequate and preserve what is adequate by modifying or abandoning whatever traditions or practices that are inadequate to improve their teaching practice. Popper claims that knowledge advances by searching for and eliminating error contained in our theory. In other words, we can improve our present theories by finding out their inadequacies. (shrink)

We have no reason to believe that reasons do not exist. Contra Bart Streumer’s recent proposal, this has nothing to do with our incapacity to believe this error theory. Rather, it is because if we know that if a proposition is true, we have no reason to believe it, then we have no reason to believe this proposition. From a different angle: if we know that we have at best misleading reasons to believe a proposition, then we have no reason (...) to believe it. This has two consequences. Firstly, coming close to believing the error theory is idle or pointless. Secondly, philosophers who argue that believing sweeping theories like determinism or physicalism is self-defeating because they are either false or believed for no reason pursue a worthwhile argumentative strategy. (shrink)

Free will sceptics deny the existence of free will, that is the command or control necessary for moral responsibility. Epicureans allege that this denial is somehow self-defeating. To interpret the Epicurean allegation charitably, we must first realise that it is propositional attitudes like beliefs and not propositions themselves which can be self-defeating. So, believing in free will scepticism might be self- defeating. The charge becomes more plausible because, as Epicurus insightfully recognised,there is a strong connection between conduct and belief—and so (...) between thecontent of free will scepticism (since it is about conduct) and the attitude of believing it. Second, we must realise that an attitude can be self- defeating relative to certain grounds. This means that it might be self-defeating to be a free will sceptic on certain grounds, such as the putative fact that we lack leeway or sourcehood. This charge is much more interesting because of the epistemic importance of leeway and sourcehood. Ultimately, the Epicurean charge of self-defeat fails. Yet, it delivers important lessons to the sceptic. The most important of them is that free will sceptics should either accept the existence of leeway or reject the principle that ‘“ought” implies “can”’. (shrink)

In this paper we provide a compact presentation of the verisimilitudinarian approach to scientific progress (VS, for short) and defend it against the sustained attack recently mounted by Alexander Bird (2007). Advocated by such authors as Ilkka Niiniluoto and Theo Kuipers, VS is the view that progress can be explained in terms of the increasing verisimilitude (or, equivalently, truthlikeness, or approximation to the truth) of scientific theories. According to Bird, VS overlooks the central issue of the appropriate grounding of scientific (...) beliefs in the evidence, and it is therefore unable (a) to reconstruct in a satisfactory way some hypothetical cases of scientific progress, and (b) to provide an explanation of the aversion to falsity that characterizes scientific practice. We rebut both of these criticisms and argue that they reveal a misunderstanding of some key concepts underlying VS. (shrink)

The view that the subject matter of epistemology is the concept of knowledge is faced with the problem that all attempts so far to define that concept are subject to counterexamples. As an alternative, this article argues that the subject matter of epistemology is knowledge itself rather than the concept of knowledge. Moreover, knowledge is not merely a state of mind but rather a certain kind of response to the environment that is essential for survival. In this perspective, the article (...) outlines an answer to four basic questions about knowledge: What is the role of knowledge in human life? What is the relation between knowledge and reality? How is knowledge acquired? Is there any a priori knowledge? (shrink)

: The distinction between science and philosophy plays a central role in methodological, programmatic and institutional debates. Discussions of disciplinary identities typically focus on boundaries or else on genealogies, yielding models of demarcation and models of dynamics. Considerations of a discipline's self-image, often based on history, often plays an important role in the values, projects and practices of its members. Recent focus on the dynamics of scientific change supplements Kuhnian neat model with a role for philosophy and yields a model (...) of the evolution of philosophy of science. This view illuminates important aspects of science and itself contributes to philosophy of science. This interactive model is general yet based on exclusive attention to physics. In this paper and two sequels, I focus on the human sciences and argue that their role in the history of philosophy of science is just as important and it also involves a close involvement of the history of philosophy. The focus is on Gestalt psychology and it points to some lessons for philosophy of science. But, unlike the discussion of natural sciences, the discussion here brings out more complication than explication, and skews certain kinds of generalizations. (shrink)

This article takes a conceptual approach to an issue of pedagogical relevance—the presence of teaching and learning moments within educational environments. We suggest sources of philosophical confusions that design patterns for the classification and creation of typologies of classroom events. We identify three foundational assumptions with the way in which classroom events are analyzed: Describing a classroom event ; Devising a procedure for co-classifying events ; Repurposing decontextualized events to fit a preferred analytic model. Hitherto these assumptions have obscured the (...) phenomenal integrity of the learning environment; since the topic sought is based on critical incidents according to analysts’ interests, but not on the actual identifying details of the setting as made available by the participants. While teaching and learning moments are generic issues, in methodological terms these matters have to be explored in their details. In our article, we align ourselves with particular research approaches, namely ethnomethodology and conversation analysis, that facilitate close analysis of ‘perspicuous settings’, such as classroom interactions, through which phenomena such as teaching and learning moments are made visible as collaborative accomplishments. (shrink)

In this paper I propose a position in the ontology of mathematics which is inspired mainly by a case study in the mathematical discipline if-theory. The main theses of this position are that mathematical objects are introduced by mathematicians and that after mathematical objects have been introduced, they exist as objectively accessible abstract objects.

We attempt a conclusive resolution of the debate over whether the principle of natural selection (PNS), especially conceived as the `principle' of the `survival of the fittest', is a tautology. This debate has been largely ignored for the past 15 years but not, we think, because it has actually been settled. We begin by describing the tautology objection, and situating the problem in the philosophical and biology literature. We then demonstrate the inadequacy of six prima facie plausible reasons for believing (...) that the tautology debate has been satisfactorily resolved (the PNS is strictly a methodological principle; scientific theories can contain tautologies; the scope of the PNS has been reduced; theories should be understood as models and not exceptionless laws; the widespread acceptance of the propensity interpretation of fitness; and the abandonment of operationalism and verificationism). We proceed to a detailed discussion of Brandon's law (D) describing the PNS, and show that law (D) seriously misrepresents the structure of evolution by natural selection. In the final sections, we provide and defend a novel reinterpretation of the structure of the principle (or, we prefer, model) of evolution by natural selection. (shrink)

The theoretical system Lyell presented in 1830 was composed of three requirements or principles: 1) the Uniformity Principle which states that past geological events must be explained by the same causes now in operation; 2) the Uniformity of Rate Principle which states that geological laws operate with the same force as at present; 3) the Steady-state Principle which states that the earth does not undergo any directional change. The three principles form a single thesis called uniformitarianism which has been repeatedly (...) questioned and which has been reputed to be unable to face the competing directional synthesis based on the theory of the earth's cooling down. As a result, the significance of Lyell's system has been reduced to a simple actualism which admits the validity of the only Uniformity Principle. I believe that the only way to understand Lyell's role in the history of science is to maintain the unity of his synthesis. To show the Newtonian roots of this synthesis I will compare Lyell's principles and Newton's Rules of Reasoning. I will conclude with an analysis of the methodological function of principles in Lyell's scientific endeavour. (shrink)