Around 540 million years ago there was a sudden, dramatic adaptive radiation known as the Cambrian Explosion. This event marked the origin of almost all of the phyla (major lineages characterized by fundamental body plans) of animals that would ever live on earth, as well the appearance of many notable features such as rigid skeletons and other hard parts, complex jointed appendages, eyes, and brains. This radical evolutionary event has been a major puzzle for evolutionary biologists since Darwin, (...) and while our understanding of it has recently improved with new fossil finds, richer molecular phylogenies, and better grasp of ecological, evolutionary, and developmental processes generally, unanswered questions remain. In this paper I argue that a basic cognitive toolkit for embodied, object-oriented, spatial cognition (what I call Basic Cognitive Embodiment) is a practical necessity for control of a large, mobile, complexly articulated body in space. This hypothesis allows us to relate the complexification of animal bodies to the complexification of perception, cognition and behavior in a way that can help to fill in gaps in our emerging picture of the Cambrian Explosion, as well as shed light on the deep evolutionary origins of the mind. (shrink)

In recent years, two schools of thought have emerged with regard to the Cambrian “explosion”. One argues that it was very quick, with phyla tumbling into existence in a virtual geological instant. The other view has a more relaxed temporal perspective. It looks to slow aeons of cryptic metazoan history, which led to a final breakthrough in the Cambrian, not in evolution but of fossilization potential. Yet both views have serious difficulties. Now, in a recent issue of (...) Biological Reviews, Graham Budd and Sören Jensen(1) argue for a third way. In an intriguing blend of functional morphology, the fossil record and cladistic thinking, they suggest that the assembly of metazoan bodyplans took place in a surprisingly straightforward manner. BioEssays 22:1053–1056, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

Phillips et al. make a compelling case for a reversal in the current paradigm in “other minds” research by considering the representation of other people's knowledge more basic than the attribution of belief. Unfortunately, they only discuss primates. In this commentary, I argue that the representation of others' knowledge is an evolutionary ancient trait, first appearing during the Cambrian explosion.

About 540 million years ago, a rapid radiation of animal phyla radically changed the Earth’s biota in a geological eye-blink. What caused this “Cambrian explosion”? Over the years, paleontologists have pointed to a wide array of different physical mechanisms as the causal “trigger” for the explosion. More recently, some paleontologists have proposed complex causal pathways to which multiple physical mechanisms are said to have contributed. Despite their variety, these answers share an assumption that a single explanation can (...) in principle be constructed that identifies some factor or confluence of factors as the cause of the Cambrian explosion. That assumption is unjustifiable. The Cambrian explosion had multiple causes, and different aspects of the event are best explained by different causes. These different causes cannot, even in principle, be integrated into a single causal explanation. We can learn much about the causes of the Cambrian explosiondor for that matter about any historical eventdbut only by attending more carefully to how we frame our causal questions about the past. (shrink)

One of the most interesting challenges facing paleobiologists is explaining the Cambrian explosion, the dramatic appearance of most metazoan animal phyla in the Early Cambrian, and the subsequent stability of these body plans over the ensuing 530 million years. We propose that because phenotypic variation decreases through geologic time, because microRNAs (miRNAs) increase genic precision, by turning an imprecise number of mRNA transcripts into a more precise number of protein molecules, and because miRNAs are continuously being added (...) to metazoan genomes through geologic time, miRNAs might be instrumental in the canalization of development. Further, miRNAs ultimately allow for natural selection to elaborate morphological complexity, because by reducing gene expression variability, miRNAs increase heritability, allowing selection to change characters more effectively. Hence, miRNAs might play an important role in shaping metazoan macroevolution, and might be part of the solution to the Cambrian conundrum. (shrink)

The Cambrian explosion is characterized by the sudden outburst of organized animal plans, which occurred circa 530 M years ago. Around that time, many forms of animal life appeared, including several which have since disappeared. There is no general consensus about “why” this happened, and why it had any form of suddenness. However, all organized animal plans share a common feature: they are triploblastic, i.e., composed of 3 layers of tissue, endoderm, ectoderm and mesoderm. I show here that, (...) within simple hypotheses, the formation of the mesoderm has intrinsically a physical exponential dynamics, leading rapidly to triploblastism, and eventually, to animal formation. A novel physico-mathematical framework including epithelium-mesenchyme transition, visco-elastic constitutive equations, and conservation laws, is presented which allows one to describe gastrulation as a self-wetting phenomenon of a soft solid onto itself. This phenomenon couples differentiation and migration during gastrulation, and leads in a closed form to an exponential scaling law for the formation of the mesoderm. Therefore, the Cambrian explosion might have started, actually, by a true visco-elastic “explosion”: the exponential run-away of mesenchymal cells. (shrink)

There are many gene families that are specific to multicellular animals. These have either diverged from ancestral genes that are shared with fungi and/or plants or evolved from an ancestral gene unique to animals. The evolution of gene families involved in cell–cell communication and developmental control has been studied to establish whether the number of member genes increased dramatically immediately prior to or in concert with the Cambrian explosion. A molecular phylogeny‐based analysis of several animal‐specific gene families has (...) revealed that gene diversification by duplication occurred during two active periods interrupted by a long intervening quiescent period. Intriguingly, the Cambrian explosion is situated in the silent period, indicating that there is no direct link between the first burst of gene diversification and the Cambrian explosion itself. The importance of gene recruitment as a possible molecular mechanism for morphological diversity, and its possible role for the Cambrian explosion, are discussed. BioEssays 23:1018–1027, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

The sudden appearance in the fossil record of the major animal phyla apparently records a phase of unparalleled, rapid evolution at the base of the Cambrian period, 545 Myr ago. This has become known as the Cambrian evolutionary ‘explosion’, and has fuelled speculation about unique evolutionary processes operating at that time. The acceptance of the palaeontological evidence as a true reflection of the evolutionary narrative has been criticised in two ways: from a reappraisal of the phylogenetic relationships (...) of the early fossils, and from predicitions of molecular divergence times, based on six appropriate metazoan genes. Phylogenetic analysis of the arthropods implies an earlier, Precambrian history for most clades, and hence an extensive period of cladogenesis unrecorded by fossils. A similar argument can be applied to molluscs, lophophorates and deuterostomes. Molecular evidence implies divergence between clades to at least 1000 Myr ago. The apparent paradox between the sudden appearance of recognisable metazoans and their extended evolutionary history might be explained by a sudden Cambrian increase in body size, which was accompanied by skeletisation. A new paradigm suggests that the ‘explosion’ in the record may have been decoupled from the evolutionary innovation. (shrink)

When and where did consciousness emerge in the course of evolution? Did it happen as recently as the past million years, for example concomitant with language or tool making in humans or primates? Or did consciousness arrive somewhat earlier, with the advent of mammalian neocortex 200 million years ago (Eccles, 1992)? At the other extreme, is primitive consciousness a property of even simple unicellular organisms of several billion years ago (e.g. as suggested by Margulis and Sagan, 1995)? Or did consciousness (...) appear at some intermediate point, and if so, where and why? Whenever it first occurred, did consciousness alter the course of evolution? (shrink)

During the early Cambrian period metazoan life forms diverged at an accelerated rate to occupy multiple ecological niches on earth. A variety of explanations have been proposed to address this major evolutionary phenomenon termed the “Cambrian explosion.” While most hypotheses address environmental, developmental, and ecological factors that facilitated evolutionary innovations, the biological basis for accelerated emergence of species diversity in the Cambrian period remains largely conjectural. Herein, we posit that morphogenesis by self‐organization enables the uncoupling of (...) genomic mutational landscape from phenotypic diversification. Evidence is provided for a two‐tiered interpretation of genomic changes in metazoan animals wherein mutations not only impact upon function of individual cells, but also alter the self‐organization outcome during developmental morphogenesis. We provide evidence that the morphological impacts of mutations on self‐organization could remain repressed if associated with an unmet negative energetic cost. We posit that accelerated morphological diversification in transition to the Cambrian period has occurred by emergence of dormant (i.e., reserved) morphological novelties whose molecular underpinnings were seeded in the Precambrian period. (shrink)

The early evolution of metazoans is a major focus of biological attention, but is the historical record revealed in the Cambrian “explosion” an accurate reflection of original events? The key questions concern the nature of the earliest animals and when they originated. One widely-mooted suggestion is that planktotrophic larvae, typified by the annelidan trochophore and echinoid pluteus, existed long before the metazoan radiations evident in the Cambrian fossil record. This idea could be consistent for recent evidence of (...) divergence times, based on molecular “clocks,” of phyla appearing well before the Cambrian. Now a surprising new discovery of eggs with blastomeres and embryos with well-defined anatomy from the Cambrian (c.530 Myr ago) of China and Siberia promises to extend the arena of debate. In one case a convincing ontogeny can be traced from eggs to adult tube-dwelling cnidarians. In the other example a possible protostome, unhatched and wrapped around the egg, shows segmentation and possibly nascent sclerites. In both, these cases development is direct, i.e., there is no evidence for any planktotrophic larval stage. The implications for our perceptions of both the Cambrian ‘explosion’ and metazoan phylogeny could be considerable. BioEssays 20:676–682, 1998.© 1998 John Wiley & Sons Inc. (shrink)

Many philosophers of biology have embraced a version of pluralism in response to the failure of theory reduction but overlook how concepts, methods, and explanatory resources are in fact coordinated, such as in interdisciplinary research where the aim is to integrate different strands into an articulated whole. This is observable for the origin of evolutionary novelty—a complex problem that requires a synthesis of intellectual resources from different fields to arrive at robust answers to multiple allied questions. It is an apt (...) locus for exploring new dimensions of explanatory integration because it necessitates coordination among historical and experimental disciplines . These coordination issues are widespread for the origin of novel morphologies observed in the Cambrian Explosion. Despite an explicit commitment to an integrated, interdisciplinary explanation, some potential disciplinary contributors are excluded. Notable among these exclusions is the physics of ontogeny. We argue that two different dimensions of integration—data and standards—have been insufficiently distinguished. This distinction accounts for why physics-based explanatory contributions to the origin of novelty have been resisted: they do not integrate certain types of data and differ in how they conceptualize the standard of uniformitarianism in historical, causal explanations. Our analysis of these different dimensions of integration contributes to the development of more adequate and integrated explanatory frameworks. (shrink)

One of the more prominent early childhood interventions focused on the development of executive function skills is Tools of the Mind. Intervention studies comparing Tools classrooms with control classrooms, however, reveal inconsistent findings for children’s EF outcomes. The current study utilizes Head Start CARES teachers assigned to the Tools of the Mind enhancement intervention and the children in their classrooms. Relations between teachers’ characteristics, training attendance and implementation, and the interaction among these factors were examined as predictors of classroom-level gains (...) in EF. Results revealed several significant moderation effects indicating that Tools implementation is related to classroom EF gains for some but not all teachers. (shrink)

Cephalopods are extraordinary molluscs equipped with vertebrate‐like intelligence and a unique buoyancy system for locomotion. A growing body of evidence from the fossil record, embryology and Bayesian molecular divergence estimations provides a comprehensive picture of their origins and evolution. Cephalopods evolved during the Cambrian (∼530 Ma) from a monoplacophoran‐like mollusc in which the conical, external shell was modified into a chambered buoyancy apparatus. During the mid‐Palaeozoic (∼416 Ma) cephalopods diverged into nautiloids and the presently dominant coleoids. Coleoids (i.e. squids, (...) cuttlefish and octopods) internalised their shells and, in the late Palaeozoic (∼276 Ma), diverged into Vampyropoda and the Decabrachia. This shell internalisation appears to be a unique evolutionary event. In contrast, the loss of a mineralised shell has occurred several times in distinct coleoid lineages. The general tendency of shell reduction reflects a trend towards active modes of life and much more complex behaviour. (shrink)

This article introduces and defends the “pathological complexity thesis” as a hypothesis about the evolutionary origins of minimal consciousness, or sentience, that connects the study of animal consciousness closely with work in behavioral ecology and evolutionary biology. I argue that consciousness is an adaptive solution to a design problem that led to the extinction of complex multicellular animal life following the Avalon explosion and that was subsequently solved during the Cambrian explosion. This is the economic trade-off problem (...) of having to deal with a complex body with high degrees of freedom, what I call “pathological complexity.” By modeling the explosion of this computational complexity using the resources of state-based behavioral and life history theory we will be able to provide an evolutionary bottom-up framework to make sense of subjective experience and its function in nature by paying close attention to the ecological lifestyles of different animals. (shrink)

A new theory about the origins of consciousness that finds learning to be the driving force in the evolutionary transition to basic consciousness. What marked the evolutionary transition from organisms that lacked consciousness to those with consciousness—to minimal subjective experiencing, or, as Aristotle described it, “the sensitive soul”? In this book, Simona Ginsburg and Eva Jablonka propose a new theory about the origin of consciousness that finds learning to be the driving force in the transition to basic consciousness. Using a (...) methodology similar to that used by scientists when they identified the transition from non-life to life, Ginsburg and Jablonka suggest a set of criteria, identify a marker for the transition to minimal consciousness, and explore the far-reaching biological, psychological, and philosophical implications. After presenting the historical, neurobiological, and philosophical foundations of their analysis, Ginsburg and Jablonka propose that the evolutionary marker of basic or minimal consciousness is a complex form of associative learning, which they term unlimited associative learning (UAL). UAL enables an organism to ascribe motivational value to a novel, compound, non-reflex-inducing stimulus or action, and use it as the basis for future learning. Associative learning, Ginsburg and Jablonka argue, drove the Cambrian explosion and its massive diversification of organisms. Finally, Ginsburg and Jablonka propose symbolic language as a similar type of marker for the evolutionary transition to human rationality—to Aristotle's “rational soul.”. (shrink)

We discuss the evolutionary transition from animals with limited experiencing to animals with unlimited experiencing and basic consciousness. This transition was, we suggest, intimately linked with the evolution of associative learning and with flexible reward systems based on, and modifiable by, learning. During associative learning, new pathways relating stimuli and effects are formed within a highly integrated and continuously active nervous system. We argue that the memory traces left by such new stimulus-effect relations form dynamic, flexible, and varied global sensory (...) states, which we call categorizing sensory states . These CSSs acquired a function: they came to act as internal “evaluators” and led to positive and negative reinforcement of new behavior. They are therefore the simplest, distinct, first-person motivational states that an animal can have. They constitute what we call basic consciousness, and are the hallmark of animals that can experience. Since associative learning has been found in many invertebrate taxa that first appeared during the Cambrian era, we propose that the processes underlying basic consciousness are phylogenetically ancient, and that their emergence may have fueled the Cambrian explosion. (shrink)

Conscious Agency is a major driver of evolution. Artificial Selection (i.e. Conscious Selection by human breeders) was the foil against which Charles Darwin defined Natural Selection. In later work, he extended Artificial Selection to other species. That ability for social (e.g. sexual) selection must have evolved. Jablonka and Ginsburg identify markers of conscious agency, such as Unlimited Associative Learning (UAL), and show that it must have existed at the time of the Cambrian Explosion. To their insights, my commentary (...) argues that the harnessing of stochasticity was also involved in the evolution of the faculty of choice in organisms. (shrink)

The Evolution of the Sensitive Soul is a landmark attempt to make progress on the problem of animal consciousness. Ginsburg and Jablonka propose a general cognitive marker of the presence of consciousness: Unlimited Associative Learning. They use this marker to defend a generous view about the distribution of consciousness in the natural world, on which a capacity for conscious experience is common to all vertebrates, many arthropods and some cephalopod molluscs. They use this inferred distribution to defend a view about (...) the evolution of consciousness, on which it has evolved at least three times, first evolved at around the time of the Cambrian explosion, and was in fact the driving force behind that explosion. In this essay review, I reflect critically on the book’s central idea: the proposal that Unlimited Associative Learning provides a general marker of consciousness. (shrink)

Veit suggests that the challenge of coordinating movement in multicellular organisms led to the evolution of a prioritizing value system, which rendered organisms complex enough to be sentient and drove the Cambrian explosion, while the absence of this evaluation system led to the demise of Ediacaran animals. In this commentary we criticize Veit’s terminology and evolutionary proposals, arguing that his terminology and evolutionary scenarios are problematic, and put forward alternative proposals. We suggest that sentience is a system property, (...) and that the evolution of sentience was the outcome of the evolution of open-ended associative learning, which included the coevolution of sensory, motor, memory, and value subsystems. We suggest that these coevolutionary system dynamics were a factor in the Cambrian explosion and contributed to the extinction of the Ediacaran biota. (shrink)

The origin of the bilaterian metazoans from radial ancestors is one of the biggest puzzles in animal evolution. A way to solve it is to identify the nature and main features of the last common ancestor of the bilaterians (LCB). Recent progress in molecular phylogeny has shown that many platyhelminth flatworms, regarded for a long time as basal bilaterians, now belong to the lophotrochozoan protostomates. In contrast, the LCB is now considered a complex organism bearing several features of modern bilaterians. (...) Here we discuss an alternative view, in which acoelomorph (Acoela + Nemertodermatida) flatworms, which do not belong to the Platyhelminthes, represent the earliest extant bilaterian clade. Sequences from ribosomal and other nuclear genes, Hox cluster genes, and reinterpretation of some morphological features strongly support the basal position of acoelomorphs arguing against a complex LCB. This reconstruction backs the old planuloid–acoeloid hypothesis and may help our understanding of the evolution of body axes, Hox genes and the Cambrian explosion. BioEssays 26:1046–1057, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

Life's Solution builds a persuasive case for the predictability of evolutionary outcomes. The case rests on a remarkable compilation of examples of convergent evolution, in which two or more lineages have independently evolved similar structures and functions. The examples range from the aerodynamics of hovering moths and hummingbirds to the use of silk by spiders and some insects to capture prey. Going against the grain of Darwinian orthodoxy, this book is a must read for anyone grappling with the meaning of (...) evolution and our place in the Universe. Simon Conway Morris is the Ad Hominen Professor in the Earth Science Department at the University of Cambridge and a Fellow of St. John's College and the Royal Society. His research focuses on the study of constraints on evolution, and the historical processes that lead to the emergence of complexity, especially with respect to the construction of the major animal body parts in the Cambrian explosion. Previous books include The Crucible of Creation (Getty Center for Education in the Arts, 1999) and co-author of Solnhofen (Cambridge, 1990). Hb ISBN (2003) 0-521-82704-3. (shrink)

How consciousness appeared much earlier in evolutionary history than is commonly assumed, and why all vertebrates and perhaps even some invertebrates are conscious. How is consciousness created? When did it first appear on Earth, and how did it evolve? What constitutes consciousness, and which animals can be said to be sentient? In this book, Todd Feinberg and Jon Mallatt draw on recent scientific findings to answer these questions—and to tackle the most fundamental question about the nature of consciousness: how does (...) the material brain create subjective experience? After assembling a list of the biological and neurobiological features that seem responsible for consciousness, and considering the fossil record of evolution, Feinberg and Mallatt argue that consciousness appeared much earlier in evolutionary history than is commonly assumed. About 520 to 560 million years ago, they explain, the great “Cambrian explosion” of animal diversity produced the first complex brains, which were accompanied by the first appearance of consciousness; simple reflexive behaviors evolved into a unified inner world of subjective experiences. From this they deduce that all vertebrates are and have always been conscious—not just humans and other mammals, but also every fish, reptile, amphibian, and bird. Considering invertebrates, they find that arthropods (including insects and probably crustaceans) and cephalopods (including the octopus) meet many of the criteria for consciousness. The obvious and conventional wisdom–shattering implication is that consciousness evolved simultaneously but independently in the first vertebrates and possibly arthropods more than half a billion years ago. Combining evolutionary, neurobiological, and philosophical approaches allows Feinberg and Mallatt to offer an original solution to the “hard problem” of consciousness. (shrink)

The explanatory challenge of sentience is known as the “hard problem of consciousness”: How does subjective experience arise from physical objects and their relations? Despite some optimistic claims, the perennial struggle with this question shows little evidence of imminent resolution. In this article I focus on the “why” rather than on the “how” of sentience. Specifically, why did sentience evolve in organic lifeforms? From an evolutionary perspective this question can be framed: “What adaptive problem(s) did organisms face in their evolutionary (...) past and how were those challenges met? I argue that sentience was a critical component of the adaptive solution (i.e., adopting an agentic stance) to increasingly complex and unpredictable demands placed on vertebrates approximately 500 million years ago (the so-called Cambrian explosion). One consequence of taking an agentic stance is that it freed the organism from its neural moorings, positioning it within phenomenal space outside its brain. (shrink)

The Burgess Shale, a set of fossil beds containing the exquisitely preserved remains of marine invertebrate organisms from shortly after the Cambrian explosion, was discovered in 1909, and first brought to widespread popular attention by Stephen Jay Gould in his 1989 bestseller Wonderful life: The Burgess Shale and the nature of history. Gould contrasted the initial interpretation of these fossils, in which they were ‘shoehorned’ into modern groups, with the first major reexamination begun in the 1960s, when the (...) creatures were perceived as ‘weird wonders’, possessing unique body plans and unrelated to modern organisms. More recently, a third phase of Burgess Shale studies has arisen, which has not yet been historically examined. This third phase represents a revolutionary new understanding, brought about, I believe, by a change in taxonomic methodology that led to a new perception of the Burgess creatures, and a new way to comprehend their relationships with modern organisms. The adoption of cladistics, and its corollary, the stem group concept, has forged a new understanding of the Burgess Shale … but has it also changed the questions we are allowed to ask about evolution? (shrink)

Creationists who object to evolution in the science curriculum of public schools often cite Jonathan Well’s book Icons of Evolution in their support (Wells 2000). In the third chapter of his book Wells claims that neither paleontological nor molecular evidence supports the thesis that the history of life is an evolutionary process of descent from preexisting ancestors. We argue that Wells inappropriately relies upon ambiguities inherent in the term ‘Darwinian’ and the phrase ‘Darwin’s theory’. Furthermore, he does not accurately distinguish (...) between the overwhelming evidence that supports the thesis of common descent and controversies that pertain to causal mechanisms such as natural selection. We also argue that Wells’ attempts to undermine the evidence in support of common descent are flawed and his characterization of the relevant data is misleading. In particular, his assessment of the ‘Cambrian explosion’ does not do justice to the fossil record. Nor do his selective references to debate about molecular and paleontological phylogenies constitute a case against common descent. We conclude that the fossil and molecular evidence is more than sufficient to warrant science educators to present common descent as a well-established scientific fact. We also argue that diagrams depicting the ‘tree of life’ can be pedagogically useful as simplified representations of the history of life. (shrink)

This chapter is concerned with the Cambrian explosion. It considers only one particular kind of explanation for the Cambrian radiation: that major innovations in animal body plan were produced from relatively few genetic changes of large phenotypic effect. It investigates the developmental genetic hypothesis of the origin and maintenance of body plans. This chapter suggests that the genetic architecture underlying body plans was not set during the Cambrian and has been immutable since. It shows that the (...) link between body plan and phylum can become blurry when the minor phyla are considered. (shrink)

For several decades, a debate has been waged over how to interpret the significance of fossils from the Burgess Shale and Cambrian Explosion. Stephen Jay Gould argued that if the “tape of life” was rerun, then the resulting lineages would differ radically from what we find today, implying that humans are a happy accident of evolution. Simon Conway Morris argued that if the “tape of life” was rerun, the resulting lineages would be similar to what we now observe, (...) implying that intelligence would still emerge from an evolutionary process. Recent methodological innovations in paleontological practice call into question both positions and suggest that global claims about the history of life, whether in terms of essential contingency or predictable convergence, are unwarranted. (shrink)

Big History has been developing very fast indeed. We are currently observing a ‘Cambrian explosion’ in terms of its popularity and diffusion. Big History courses are taught in the schools and universities of several dozen countries, including China, Korea, the Netherlands, the USA, India, Russia, Japan, Australia, Great Britain, Germany, and many more. The International Big History Association (IBHA) is gaining momentum in its projects and membership. Conferences are beginning to be held regularly (this edited volume has been (...) prepared on the basis of the proceedings of the International Big History Association Inaugural Conference [see below for details]). Hundreds of researchers are involved in studying and teaching Big History. (shrink)

Logic has traditionally been construed as a normative discipline; it sets forth standards of correct reasoning. Explosion is a valid principle of classical logic. It states that an inconsistent set of propositions entails any proposition whatsoever. However, ordinary agents presumably do — occasionally, at least — have inconsistent belief sets. Yet it is false that such agents may, let alone ought to, believe any proposition they please. Therefore, our logic should not recognize explosion as a logical law. Call (...) this the ‘normative argument against explosion’. Arguments of this type play — implicitly or explicitly — a central role in motivating paraconsistent logics. Branden Fitelson, in a throwaway remark, has conjectured that there is no plausible ‘bridge principle’ articulating the normative link between logic and reasoning capable of supporting such arguments. This paper offers a critical evaluation of Fitelson’s conjecture, and hence of normative arguments for paraconsistency and the conceptions of logic’s normative status on which they repose. It is argued that Fitelson’s conjecture turns out to be correct: normative arguments for paraconsistency probably fail. (shrink)

(2014). Explosive Population Growth in Tropical Africa: Crucial Omission in Development Forecasts—Emerging Risks and Way Out. World Futures: Vol. 70, No. 2, pp. 120-139.

In this paper, I develop a novel account of ideological kinds. I first present some conceptual territory regarding the use of Occam’s Razor in minimizing ontological commitments. I then present the analogous device for minimizing ideological commitments, what I call the Comb. I argue that metaphysicians ought to use both or none at all. This means that those who endorse a principle of ontological parsimony ought to also endorse some principle of ideological parsimony, where we ought to prefer the metaphysical (...) theory that employs less ideology. In support of one such principle, I propose a novel account of ideological kinds. I individuate ideological kinds based on the satisfaction of two conditions: interdefinability and sameness of syntactic category. Ultimately, I think this account is the best available. It does, however, produce surprising results. For instance, my account shows that quantifier pluralism is ideologically parsimonious. I end by replying to some objections. (shrink)

One strategy for defending paraconsistent logics involves raising ‘normative arguments’ against the inference rule explosion. Florian Steinberger systematically criticises a wide variety of formulations of such arguments. I argue that, for one such formulation, Steinberger’s criticisms fail. I then sketch an argument, available to those who deny dialetheism, in defence of the formulation in question.

ㅤThis article is part of a symposium on Jc Beall's "Christ-A Contradiction.".

Argument“How should a modern artist react to the atomic age?” Time magazine posed this question in 1952 to open a review of an exhibition of paintings inspired by the “explosion of the atomic bomb” and by the “discovery of nuclear energy.” The energetic paintings of the Italian Spatial Movement were, according to Time, “almost as explosive as the bomb itself.” “Explosiveness” was a defining feature of much 1950s art, whose main impulse, gestural abstraction, has previously been understood as the (...) urgent expression of the artist's subjectivity. This paper argues that explosiveness in art can also be seen as an “expression” of the realities of the nuclear era. Postwar artists were ambivalent about the explosive forces, both liberating and devastating, that lay within the atom. Toward the end of the 1950s, no longer content merely to represent atomic disintegration, some artists went so far as to propose the outright self-destruction of the work of art as the only fitting means of expression in the atomic age.One must – and this is not an exaggeration – keep in mind that we are living in the atomic age, where everything material and physical could disappear from one day to another, to be replaced by nothing but the ultimate abstraction imaginable.– Yves Klein 1958. (shrink)

A calculus for classical propositional sequents is introduced that consists of a restricted version of the cut rule and local variants of the logical rules. Employed in the style of proof search, this calculus explodes a given sequent into its elementary structural sequents—the topmost sequents in a derivation thus constructed—which do not contain any logical constants. Some of the properties exhibited by the collection of elementary structural sequents in relation to the sequent they are derived from, uniqueness and unique representation (...) of formula occurrences, will be discussed in detail. Based on these properties it is suggested that a collection of elementary structural sequents constitutes the purely structural representation of the sequent from which it is obtained. (shrink)

Science and revelation have been presented as two books with the same “author,” their reconciliation being called “concordism.” Teilhard opposed concordism, insisting that supposed “revelations” be treated as scientific hypotheses to be verified or not in experience. Applying his criterion for truth (Does it bring “coherence and fecundity” to the phenomena?) to Christian revelation, he told of finding “an explosion of dazzling flashes.” So Teilhard spoke of the hypothesis as the supreme spiritual act wherein the dust of experience takes (...) on form and is kindled at the fire of knowledge. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Ethics & the Environment 8.2 (2003) 71-79 [Access article in PDF] "Explosion" Greta Gaard I. In the beginning there was only water, and you were a part of it. Never mind what else you have heard. This was your first relationship, your connection to water. And the quality of this relationship, the character of your beliefs about water, shapes all relationships in your life. The way you do (...) one thing is the way you do everything. You cannot separate one relationship from another, treat this water with reverence, this water with waste. Because water returns. Water knows there are no separations. You too should know this, for water has been teaching you, from the beginning.Imagine a creek flowing through the length of your life, from your birth to your death. Yes, your death. Water precedes you, water survives you. Consider the silence of blue-ice glaciers, ancient in their solitude, melting. Each winter the snowfall thick and wet, fluffy, or crisp and dry. Each spring the snows melting, glaciers growing and melting. Water flows down pine needles and cedar bark, flows down rocks and fallen logs, flows through moss and soil and sand.The lake gathers rainfall, gathers snowmelt and the plenitude of creeks. The lake overflows, spills, falls, exuberance of fullness, joy in motion, streaming downhill now, swelling the creek bed where it has made this journey so many times before.You have never seen this creek, the hidden water that flows through your days and nights, from one season to the next. Without it you would not live. You rely on this unseen water to flow forever. It has flowed here [End Page 71] before you were born, before you stepped into its flow, and you imagine it will outlast you, outlast whatever you might do to this water. You believe it is limitless, unending. You know its persistent force has carved rocks because you can see them, see the way water flows through stone, leaving its imprint in kettles, in the basins of water where rocks circulate, in the interlaced fingers of water and stone embracing at the falls.Water becomes you. But Narcissus-like, you look at water and see only your self. You believe you are alone. You are afraid. You need to con-trol this fear, this aloneness, this terrifying separation. You see the power of water and you want power. Power will give you control. You build dams and concrete channels and ditches, believing that by doing this you will control the power of water, the fertility of water, the fear of your separation. But water is patient. There are laws that govern the way of water, the ways of energy and power, the ways of land. There are consequences. Water bears no grudge, extracts no retribution. Your own actions, skillful or unskillful, determine the outcome. Your own relationship to water will poison you or save you. You decide.You believe blocking the flow of water gives you power.You believe blocking the flow of feeling gives you power.You believe harnessing the animals, fencing off the land gives you power. And for awhile, these strategies work.But there are consequences. That which is diverted, divided, suppressed, always returns with greater force, and when it returns, no one can control it. No one. II. Imagine a family. Picture the elders first. How many do you see? Where are the children? The sisters and brothers, aunts and uncles, cousins and nephews and grandchildren? How many people are needed to form a family? Can you be a family of one?Look at it another way: is there a limit to the relations of family? Is there a certain number of people allowed in a family until a limit is reached? Do you say, "Families may only have ten people"? "The eleventh person will not be included." Or do you point to the basis of inclusion, the things that bind you, one to another, and say, "Yes, this person too"?How do you recognize a family?Do family members have to pulse with the same blood, or will love create a family where the blood... (shrink)

The twentieth-century logical mainstream, derived from works by Łukasiewicz and Scholz, pictures the history of logic for the most part as the prehistory of Boolean–Fregean mathematical logic. Particularly, with respect to classical propositional calculus, the Stoic logic has been pictured as an early stage of it and Aristotle's or the Peripatetics' logic as a theory that assumes it. Although it was not emphasised, it follows that the ancient logics contain the principle of explosion. In the endmost quarter of the (...) twentieth century, a competitive view began to spread to the effect that the ancient systems of logic were paraconsistent or relevantistic. In the twenty-first century, the latter view prevails and has every chance of becoming a new orthodoxy. It is claimed that although in Łukasiewicz's argument for the classicality of ancient logics, there are gaps, it may be demonstrated that the ancient logics contain the principle of explosion. (shrink)

The task of my inquiry is to lay out the main lines of Eugen Fink’s reading of Kant, focusing on his interpretation of the Transcendental Dialectic. In the first part, I explain Fink’s claim that the Transcendental Dialectic represents the very heart of the Kantian project, in as much it is in this section of the first Critique that the question of totality (on Fink’s account, the driving impetus of this work) first comes to the forefront. Secondly, I undertake an (...) examination of Fink’s argument regarding the proper outcome of the “Antinomies of Pure Reason,” according to which the failure of the attempts to determine the world with “innerworldly models” is not a sufficient reason to contend that the world is merely a subjective idea. Finally, I discuss Fink’s thesis concerning the construction of the “Transcendental Ideal” according to which the transition from the omnitudo realitatis to the ens realissimum is not necessary (neither objectively, nor subjectively). In this regard, Fink’s project can be understood as an attempt to think the omnitudo realitatis for itself, prior to and independent from any realization in a being (be it a supreme one). (shrink)

Not only in its conceptual reconstruction but also in the straightforward application of Badioursquo;s thought its problems and tensions come to light. This paper thus sets out to identify a generic truth procedure in the domain of art; specifically within theatre starting out from the Meyerhold-event and tracing enquiries in the work of Artaud and Brecht. It turns out once one follows the lines of further enquiries one ends up sketching an explosive genealogy that gives rise to the concept of (...) an art of presentation transgressing the boundaries of theatre, art and philosophy. (shrink)

Not only in its conceptual reconstruction but also in the straightforward application of Badioursquo;s thought its problems and tensions come to light. This paper thus sets out to identify a generic truth procedure in the domain of art; specifically within theatre starting out from the Meyerhold-event and tracing enquiries in the work of Artaud and Brecht. It turns out once one follows the lines of further enquiries one ends up sketching an explosive genealogy that gives rise to the concept of (...) an art of presentation transgressing the boundaries of theatre, art and philosophy. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Ethics & the Environment 8.2 (2003) 71-79 [Access article in PDF] "Explosion" Greta Gaard I. In the beginning there was only water, and you were a part of it. Never mind what else you have heard. This was your first relationship, your connection to water. And the quality of this relationship, the character of your beliefs about water, shapes all relationships in your life. The way you do (...) one thing is the way you do everything. You cannot separate one relationship from another, treat this water with reverence, this water with waste. Because water returns. Water knows there are no separations. You too should know this, for water has been teaching you, from the beginning.Imagine a creek flowing through the length of your life, from your birth to your death. Yes, your death. Water precedes you, water survives you. Consider the silence of blue-ice glaciers, ancient in their solitude, melting. Each winter the snowfall thick and wet, fluffy, or crisp and dry. Each spring the snows melting, glaciers growing and melting. Water flows down pine needles and cedar bark, flows down rocks and fallen logs, flows through moss and soil and sand.The lake gathers rainfall, gathers snowmelt and the plenitude of creeks. The lake overflows, spills, falls, exuberance of fullness, joy in motion, streaming downhill now, swelling the creek bed where it has made this journey so many times before.You have never seen this creek, the hidden water that flows through your days and nights, from one season to the next. Without it you would not live. You rely on this unseen water to flow forever. It has flowed here [End Page 71] before you were born, before you stepped into its flow, and you imagine it will outlast you, outlast whatever you might do to this water. You believe it is limitless, unending. You know its persistent force has carved rocks because you can see them, see the way water flows through stone, leaving its imprint in kettles, in the basins of water where rocks circulate, in the interlaced fingers of water and stone embracing at the falls.Water becomes you. But Narcissus-like, you look at water and see only your self. You believe you are alone. You are afraid. You need to con-trol this fear, this aloneness, this terrifying separation. You see the power of water and you want power. Power will give you control. You build dams and concrete channels and ditches, believing that by doing this you will control the power of water, the fertility of water, the fear of your separation. But water is patient. There are laws that govern the way of water, the ways of energy and power, the ways of land. There are consequences. Water bears no grudge, extracts no retribution. Your own actions, skillful or unskillful, determine the outcome. Your own relationship to water will poison you or save you. You decide.You believe blocking the flow of water gives you power.You believe blocking the flow of feeling gives you power.You believe harnessing the animals, fencing off the land gives you power. And for awhile, these strategies work.But there are consequences. That which is diverted, divided, suppressed, always returns with greater force, and when it returns, no one can control it. No one. II. Imagine a family. Picture the elders first. How many do you see? Where are the children? The sisters and brothers, aunts and uncles, cousins and nephews and grandchildren? How many people are needed to form a family? Can you be a family of one?Look at it another way: is there a limit to the relations of family? Is there a certain number of people allowed in a family until a limit is reached? Do you say, "Families may only have ten people"? "The eleventh person will not be included." Or do you point to the basis of inclusion, the things that bind you, one to another, and say, "Yes, this person too"?How do you recognize a family?Do family members have to pulse with the same blood, or will love create a family where the blood... (shrink)