Prior to the twentieth century, theories of knowledge were inherently perceptual. Since then, developments in logic, statis- tics, and programming languages have inspired amodal theories that rest on principles fundamentally different from those underlying perception. In addition, perceptual approaches have become widely viewed as untenable because they are assumed to implement record- ing systems, not conceptual systems. A perceptual theory of knowledge is developed here in the context of current cognitive science and neuroscience. During perceptual experience, association areas in the brain capture bottom-up patterns of activation in sensory-motor areas. Later, in a top-down manner, association areas partially reactivate sensory-motor areas to implement perceptual symbols. The stor- age and reactivation of perceptual symbols operates at the level of perceptual components - not at the level of holistic perceptual expe- riences. Through the use of selective attention, schematic representations of perceptual components are extracted from experience and stored in memory (e.g., individual memories of green, purr, hot). As memories of the same component become organized around a com- mon frame, they implement a simulator that produces limitless simulations of the component (e.g., simulations of purr). Not only do such simulators develop for aspects of sensory experience, they also develop for aspects of proprioception (e.g., lift, run) and introspec- tion (e.g., compare, memory, happy, hungry). Once established, these simulators implement a basic conceptual system that represents types, supports categorization, and produces categorical inferences. These simulators further support productivity, propositions, and ab- stract concepts, thereby implementing a fully functional conceptual system. Productivity results from integrating simulators combinato- rially and recursively to produce complex simulations. Propositions result from binding simulators to perceived individuals to represent type-token relations. Abstract concepts are grounded in complex simulations of combined physical and introspective events. Thus, a per- ceptual theory of knowledge can implement a fully functional conceptual system while avoiding problems associated with amodal sym- bol systems. Implications for cognition, neuroscience, evolution, development, and artificial intelligence are explored.

/pdf/perceptual-symbol-systems-4spsk97r61.pdf

Perceptual symbol systems.

The evidentiary basis of the currently accepted classification of living amphibians is discussed and shown not to warrant the degree of authority conferred on it by use and tradition. A new taxonomy of living amphibians is proposed to correct the deficiencies of the old one. This new taxonomy is based on the largest phylogenetic analysis of living Amphibia so far accomplished. We combined the comparative anatomical character evidence of Haas (2003) with DNA sequences from the mitochondrial transcription unit H1 (12S and 16S ribosomal RNA and tRNAValine genes, ≈ 2,400 bp of mitochondrial sequences) and the nuclear genes histone H3, rhodopsin, tyrosinase, and seven in absentia, and the large ribosomal subunit 28S (≈ 2,300 bp of nuclear sequences; ca. 1.8 million base pairs; x = 3.7 kb/terminal). The dataset includes 532 terminals sampled from 522 species representative of the global diversity of amphibians as well as seven of the closest living relatives of amphibians for outgroup comparisons. The...

https://bioone.org/journals/Bulletin-of-the-American-Museum-of-Natural-History/volume-2006/issue-297/0003-0090(2006)297[0001:TATOL]2.0.CO;2/THE-AMPHIBIAN-TREE-OF-LIFE/10.1206/0003-0090(2006)297[0001:TATOL]2.0.CO;2.pdf

The amphibian tree of life

Hydrothermal carbonization can be defined as combined dehydration and decarboxy lation of a fuel to raise its carbon content with the aim of achieving a higher calorific value. It is realized by applying elevated temperatures (180–220°C) to biomass in a suspension with water under saturated pressure for several hours. With this conversion process, a lignite-like, easy to handle fuel with well-defined properties can be created from biomass residues, even with high moisture content. Thus it may contribute to a wider application of biomass for energetic purposes. Although hydrothermal carbonization has been known for nearly a century, it has received little attention in current biomass conversion research. This review summarizes knowledge about the chemical nature of this process from a process design point of view. Reaction mechanisms of hydrolysis, dehydration, decarboxylation, aromatization, and condensation polymerization are discussed and evaluated to describe important operational parameters qualitatively. The results are used to derive fundamental process design improvements. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd

Hydrothermal carbonization of biomass: A summary and discussion of chemical mechanisms for process engineering

Reports the APA Presidential address delivered at the Chicago convention, August 1975. Urban humanity is considered as a product of both biological and social evolution. Evolutionary genetics shows that when there is genetic competition among the cooperators (as for humans but not for the social insects), great limitations are placed upon the degree of socially useful, individually self-sacrificial altruism that biological evolution can produce. Human urban social complexity is a product of social evolution and has had to counter with inhibitory moral norms the biological selfishness which genetic competition has continually selected. Because the issues are so complex and the available data are so uncompelling, all of this should be interpreted more as a challenge to an important new area for psychological research than as established conclusions. It is emphasized, however, that these are important issues to which psychology should give much greater attention, and that scientific reasons exist for believing that there can be profound system wisdom in the belief systems our social tradition has provided us with. (31/2 p ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)

On the conflicts between biological and social evolution and between psychology and moral tradition.

Social Darwinism in American Thought

IT MAY be safely assumed that, two thousand years ago, before Cæsar set foot in southern Britain, the whole country-side visible from the windows of the room in which I write, was in what is called "the state of nature". Except, it may be, by raising a few sepulchral mounds, such as those which still, here and there, break the flowing contours of the downs, man's hands had made no mark upon it; and the thin veil of vegetation which overspread the broad-backed heights and the shelving sides of the coombs was unaffected by his industry. The native grasses and weeds, the scattered patches of gorse, contended with one another for the possession of the scanty surface soil; they fought against the droughts of summer, the frosts of winter, and the furious gales which swept, with unbroken force, now from the Atlantic, and now from the North Sea, at all times of the year; they filled up, as they best might, the gaps made in their ranks by all sorts of underground and overground animal ravagers. One year with another, an average population, the floating balance of the unceasing struggle for existence among the indigenous plants, maintained itself. It is as little to be doubted, that an essentially similar state of nature prevailed, in this region, for many thousand years before the coming of Cæsar; and there is no assignable reason for denying that it might continue to exist through an equally prolonged futurity, except for the intervention of man.

Evolution and Ethics

/pdf/science-and-education-340a4b1u75.pdf

Science and Education

Huxley was one of the first adherents to Darwin's theory of evolution by natural selection and advanced its acceptance by scientists and the public. Man's Place in Nature was explicitly directed against Richard Owen, who had claimed that there were distinct differences between human brains and those of apes. Huxley demonstrated that ape and human brains were fundamentally similar in every anatomical detail, thus applying evolution to the human race.

Man's Place in Nature

In 1863, the biologist and educator Thomas Henry Huxley published Evidence as to Man's Place in Nature, a compilation of his public lectures on Darwin's theory of evolution — specifically the controversial idea of the ape ancestry of humans. An energetic supporter of Darwin, Huxley's argues that in order to understand the universe, everyone must know their place in the natural world. The book is divided into three parts, each written with the aim of persuading lay audiences. The first covers earlier human beliefs about exotic animals, especially 'man-like' apes. In Part 2, Huxley suggests that every animal on Earth is related in that all go through developmental stages from an egg, whether the animal is 'a silkworm or a school-boy'. Part 3 involves a discussion of recently discovered Neanderthal bones and compares prehistoric craniums to modern human skulls.

Thomas Henry Huxley

Papers

Evolution and Ethics

Science and Education

Man's Place in Nature

Evidence as to man's place in nature.

The crayfish;: An introduction to the study of zoology