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Additions to the Bibliography on Mind and Consciousness)

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Laird John, Rosenbloom Paul & Newell Allen: UNIVERSAL SUBGOALING AND CHUNKING (Kluwer Academics, 1986)
The book describes in detail an architecture (SOAR) for general intelligence. The universal weak method is an organizational framework whereby knowledge determines the weak methods employed to solve the problem, i.e. knowledge controls the behavior of the rational agent. Universal subgoaling is a scheme whereby goals can be created automatically to deal with the difficulties that the rational agent encounters during problem solving.
The engine of the architecture is driven by production rules that fire in parallel and represent task-dependent knowledge. The architecture maintains a context which is made of four slots: goal, problem space, state and operator. A fixed set of production rules determines which objects have to become current, i.e. fill those slots. In other words, they determine the strategic choices to be made after each round of parallel processing.
A model of practice is developed based on the concept of chunking, which is meant to produce the power law of practice that characterizes the improvements in human performance during practice at a given skill. Rosenbloom describes the XAPS3 system, which was designed to model goal hierarchies and chunking. Each task has a goal hierarchy. When a goal is successfully completed, a chunk that represent the results of the task is created. In the next instance of the goal, the system will not need to fully process it as the chunk already contains the solution. The process of chunking proceeds bottom-up in the goal hierarchy. The process of chunking eventually leads to a chunk for the top-level goal for every situation that it can encounter.

Lakoff George: PHILOSOPHY IN THE FLESH (Basic, 1998)
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Lakoff George: METAPHORS WE LIVE BY (Chicago Univ Press, 1980)
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Lakoff George: WOMEN, FIRE AND DANGEROUS THINGS (Univ of Chicago Press, 1987)
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Lakoff George: MORE THAN COOL REASON (University of Chicago Press, 1989)
While studying poetic metaphors, Lakoff emphasizes that metaphor is not only a matter of words, but a matter of thought, that metaphor is central to our understanding of the world and the self. Poetry is simply the art of extending metaphors and therefore the mind's power of grasping concepts.

Richard Lane & Lynn Nadel: COGNITIVE NEUROSCIENCE OF EMOTION (Oxford Univ Press, 2000)
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Langacker Ronald: CONCEPT, IMAGE AND SYMBOL (Mouton de Gruyter, 1991)
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Langacker Ronald: FOUNDATIONS OF COGNITIVE GRAMMAR (Stanford Univ Press, 1986)
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Langton Christopher: ARTIFICIAL LIFE (Addison-Wesley, 1989)
Proceedings of the first A-life workshop at the Santa Fe` Institute. Chris Langton pretty much invented the field (or, at least, gave it a name) in 1987.
In Langton's own theory, living beings and cellular automata have in common the transfer and conservation of information. Living organisms use information, besides matter and energy, in order to grow and reproduce. In living systems the manipulation of information prevails over the manipulation of energy.
Life depends on a balance of information: too little information is not enough to produce life, too much can actually be too difficult to deal with. Life is due to a reasonable amount of information that can move and be stored. Life happens at the edge of chaos.
Complexity is an inherent property of life. And life is a property of the organization of matter.
In order to build artificial life Langton defines a "generalized genotype" as the set of low-level rules serving as the genetic blueprint and the "generalized phenotype" as the structure that is created from those instructions.

Langton Christopher: ARTIFICIAL LIFE II (Addison-Wesley, 1992)
Proceedings of the second A-life workshop at the Santa Fe` Institute.

Langton Christopher: ARTIFICIAL LIFE (MIT Press, 1995)
A collection of articles by various authors originally published in the Artificial Life journal.

Larson Richard & Segal Gabriel: KNOWLEGDE OF MEANING (MIT Press, 1995)
A monumental introduction to truth-theoretic semantics for natural languages. Unlike most semantic studies, which are based on Montague's semantics, this one is from Davidson's perspective.

Lashley Karl Spencer: BRAIN MECHANISMS AND INTELLIGENCE (Dover, 1963)
This 1929 study set the standard for cognitive neurophysiology and psychology. The 1963 reissue comes with a preface by Donald Hebb that puts Lashley's achievements in perspective.
In Lashley's mnemonic distribution model each mnemonic function is not localized in a specific point of the mind, but distributed over the entire mind.
Later Lashley also noted how the dualism between mind and brain resembles the one between waves and particles. A memory in the brain behaves like a wave in an electromagnetic field.

Laszlo, Ervin & Combs, Allan: CHANGING VISIONS (1996)
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Laszlo, Ervin: INTRODUCTION TO SYSTEMS PHILOSOPHY (Gordon & Breach, 1972)
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Lavine Robert: NEUROPHYSIOLOGY (Collamore, 1983)
A comprehensive introduction to the neuron, the structure of the brain, senses and to higher cognitive functions.

Lavie Piretz: THE ENCHANTED WORLD OF SLEEP (Yale Univ Press, 1996)
Lavie studies sleep in animals and proves that birds display REM sleep while some mammals (notably the dolphin) do not.

Layzer David: COSMOGENESIS (Oxford University Press, 1990)
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Lazarus Richard: EMOTION AND ADAPTATION (Oxford Univ Press, 1991)
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Lazarus Richard & Lazarus Bernice: PASSION AND REASON (Oxford Univ Press, 1994)
Lazarus reiterates his point that emotions are as rational as anything can be in a language accessible to anybody.

Ledoux Joseph & William Hirst: MIND AND BRAIN (Cambridge Univ Press, 1986)
A collection of articles on perception, attention, memory and emotion that are organized as debates between psychologists and neurobiologists.

LeDoux Joseph: THE EMOTIONAL BRAIN (Simon & Schuster, 1996)
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LeDoux Joseph: SYNAPTIC SELF (Penguin, 2002)
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Lehnert Wendy: STRATEGIES FOR NATURAL LANGUAGE LANGUAGE (Lawrence Erlbaum, 1982)
A practical textbook on natural language processing in the conceptual dependency tradition. Each chapter is written by an authority of the field. Includes Steven Small's word-based parser, Gerald DeJong's FRUMP system, Wilensky's PAM system, Wendy Lehnert's plot units, Schank's MOPs. Jerry Hobbs writes about coherence in discourse. Yorick Wilks discusses procedural semantics.

Leiser David & Gillieron Christiane: COGNITIVE SCIENCE AND GENETIC EPISTEMOLOGY (Plenum Press, 1989)
The book analyzes the relations between procedures and structures from a Piagetian perspective and attempts to bridge a gap between cognitive psychology and artificial intelligence.

Lenat Douglas: BUILDING LARGE KNOWLEDGE-BASED SYSTEMS (Addison-Wesley, 1990)
The book describes the CYC system, whose goal is to represent common knowledge (i.e., develop a global ontology) and perform common-sense reasoning (i.e., employ a set of reasoning methods as a set of first principles) on large knowledge bases. to explain
Units of knowledge for common sense are units of "reality by consensus": all the things we know and we assume everybody knows; i.e., all that is implicit in our acts of communication. A principle of economy of communications states the need to minimize the acts of communication and maximize the information that is transmitted. World regularities belong to this tacitly accepted knowledge.

Lenneberg Eric: BIOLOGICAL FOUNDATIONS OF LANGUAGE (Wiley, 1967)
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Leonard, Andrew: BOTS (Penguin Books, 1998)
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LePore Ernest: NEW DIRECTIONS IN SEMANTICS (Academic Press, 1987)
A collection of articles on semantics, including Hintikka's game-theoretical semantics, Gilbert Harman's conceptual role semantics (the ultimate source of meaning is the functional role that symbols play in thought) and dual aspect semantics (which contain one theory relating language to the world and one theory relating language to the mind).

Lesniewski Stanislaw: COLLECTED WORKS (Kluwer Academic, 1991)
In the Thirties the polish logician Lesniewski noted that in any language containing its semantics logical laws cannot hold consistently. A contradiction can be avoided only by reconstructing the object language through hierarchical levels, or metalanguages. This is similar to Russell's conclusion that some hierarchy is necessary for a system to be coherent. Lesniewski developed a hierarchy of categories (a grammar of semantic categories). Lesniewski's system consists of three axiomatic theories: protothetic (a calculus of equivalent propositional functions, with a single axiom), ontology (a calculus of classes in terms of a theory of nominal predication, with a single axiom) and mereology (based on the part-whole relation, containing rules to avoid paradoxes). Functorial categories can be generated from a set of basic categories (the propositions defined by the single axiom of protothetic and the nouns defined by the single axiom of ontology) and are categories of functions from certain arguments to certain values.

Levin Samuel: METAPHORIC WORLDS (Yale University Press, 1988)(Lawrence Erlbaum, 1991)
Levin argues that metaphors create metaphoric worlds in which they have literal and true referents. Metaphoric expressions, therefore, are to be taken literally.

Levine Daniel: INTRODUCTION TO NEURAL AND COGNITIVE MODELING (Lawrence Erlbaum, 1991)
A broad survey of cognitive science from a neuroscientific perspective. After a historical outline (McCulloch-Pitts neurons, Hebb's law, Rosenblatt's perceptron, etc), Levine details algorithms (and physiological justifications) for associative learning, competition, conditioning, categorization, representation. All the main connectionist models are surveyed. The book provides a detailed, technical compendium of data and ideas in the field.

Levine, Joseph: PURPLE HAZE (Oxford Univ Press, 2000)
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Levinson Stephen: PRAGMATICS (Cambridge Univ Press, 1983)
An excellent and relatively accessible introduction to pragmatics.
Levinson surveys the issues of pragmatics, defined essentially as the relationship between language and context. Approaches to indexicals or deixis (Fillmore, Lyons, Lakoff), implicatures (Grice, Gazdar), presupposition (Stalnaker, Karttunen), speech acts (Austin, Searle), and discourse analysis are dealt with at length. This is the best introduction to the theories that emerged during the late Seventies.

Levy Steven: ARTIFICIAL LIFE (Pantheon, 1992)
An introduction for the wider audience to the world of artificial life. Includes history of the field (from Von Neumann to viruses), biographies of its visionaries (Kauffman, Holland, Hawkins, Ray, Brooks) and simplified presentations of their theories.

Lewin Roger: COMPLEXITY (Macmillan, 1992)
Complexity is presented as a discipline that can unify the laws of physical, chemical, biological, social and economic phenomena through the simple principle that all things in nature are driven to organize themselves into patterns. The book, written in conversational english, devotes much time to describing the protagonists of the field and relating interviews in a celebrity-centered fashion.

Lewis Clarence-Irving: SYMBOLIC LOGIC (Mineola, 1932)
In Lewis' modal logic a proposition is necessary if it is true in every possible world, it is possible if it is true in at least one possible world. "Necessity" and "possibility" are modal operators, i.e. they operate on logical expressions just like logical connectives. The two modal operators are dual (one can be expressed in terms of the other), thereby reflecting the dualism of the two corresponding quantificators (existential and universal). A modal logic is built by adding a few axioms containing the modal operators to the axioms of a non-modal logic.

Lewis David: COUNTERFACTUALS (Harvard Univ Press, 1973)
Lewis uses possible-world semantics in his theory of counterfactuals. Lewis defines a pair of conditional operators ("if it were the case that, then it would be the case that" and "if it were the case that, then it might be the case that"), which can be defined one in terms of the other. Counterfactuals are not strict conditionals (material conditionals preceded by a necessity operator), but rather "variably" strict conditionals (a counterfactual is as strict as it must be to escape vacuity and no stricter).
Lewis then defends possible worlds and claims that each possible world is as "real" as ours.
Lewis also compares his theory to Stalnaker's own, which is also based on possible worlds.

Lewis David: PHILOSOPHICAL PAPERS (Oxford Press, 1983)
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Lewis David K.: ON THE PLURALITY OF WORLDS (Basil Blackwell, 1986)
Lewis advocates an indexical theory of actuality. Every possible world is actual from its own point of view, and every possible world is merely possible from the point of view of other worlds. Worlds are never causally related to other worlds. The isolation of possible worlds constitutes their being merely possible relative to each other.
A proposition is a function from possible worlds to truth-values. Each world provides a truth value for a proposition.

Lewontin Richard: THE GENETIC BASIS OF EVOLUTIONARY CHANGE (Columbia University Press, 1974)
It is not yet clear which percentage of evolutionary change is due to natural selection and which is due to random events. Modern evolutionary genetics stems from the merging of two traditions, the Darwinian and the Mendelian, both of which take variation as the crucial aspect of life. The Darwinian view can be summarized as "evolution is the conversion of variation between individuals into variation between populations and species in time and space". The paradox is that Mendelian theory dictates the frequencies of genotypes as the appropriate genetic description of a population, whereas variation is much more important. "What we can measure is uninteresting and what we are interested in is unmeasurable". Most theories of genetic variation in populations (allelic variation) are also theories of natural selection. Variation and selection turn out to be dual aspects of the same problem.
Even worse is the situation with respect to "the origin of species", i.e. theories of the genetic changes that occur in species formation. Geographic isolation (or, better, ecological divergence) is recognized as the preliminary stage, causing the appearance of genetic differences sufficient to restrict severely the genetic exchange with other populations (reproductive isolation). The second stage occurs when isolated populations come into contact and the third stage starts when the newly formed species continue to develop independently.
Lewontin reviews evidence in favor of each theory. His conclusion, in ragarding the genome as the uit of selection, is that "context and interaction are of essence".

Lewontin Richard: HUMAN DIVERSITY (W.H.Freeman, 1981)
Each organism is the subject of continous development throughout its life and such development is driven by mutually interacting genes and environment. Genes per se cannot determine the phenotype, capacity or tendencies.
The organism is both the subject and the object of evolution. Organisms construct environments that are the conditions for their own further evolution and for the evolutions of nature itself towards new environments. Organism and environment mutually specifify each other.

Leyton Michael: SYMMETRY, CAUSALITY, MIND (MIT Press, 1992)
Leyton's idea is that shape is used by the mind to recover the past. Shape is time. Shape equals the history that created it.
By studying the psychological relationship between shape and time, Leyton offers a working model of how perception is converted into memory.
There is a relationship between perceived asymmetry, inferred history and environmental energy. The energy of a system corresponds to memory of the causal interactions that transferred to the system.Shape, or asymmetry, is a memory of the energy transferred to an object in causal interactions.
All vision is the recovery of the past: vision simply "unlocks" time from the image. In general, perceptual representations are representations of stimuli in terms of causal histories. This is also true of cognitive representations.
Any cognitive representation is the description of a stimulus as a state in a history that causally explains the stimulus to the organism. A cognitive system is a system that creates and manipulates causal explanations.

Li Ming & Vitanyi Paul: AN INTRODUCTION TO KOLMOGOROV COMPLEXITY (Springer-Verlag, 1993)
The second edition of the monumental manual on the subject.
The amount of information in a finite string is the size of the shortest program that computes the string. This is the "Kolmogorov complexity" of the string. Objects that contain regularities have a description that is shorter than themselves. Algorithmic information theory is the discipline that deals with the quantity of information in objects. Probability theory, instead, cannot define randomness. Probability theory says nothing about the meaning of a probability: a probability is simply a measure of frequency. A Kolmogorov random string is one that cannot be compressed.

Lieberman Phipip: THE BIOLOGY AND EVOLUTION OF LANGUAGE (Harvard Univ Press, 1984)
Language is found to be a by-product of the neural processes that underly cognition in general (unlike Chomsky's vision of separate "language organs"). The only language-specific processes are essentially those that contribute to speech, and they evolved from processes that are common to many animals. Speech, not syntax, is the fulcrum of language.

Lieberman Philip: UNIQUELY HUMAN (Harvard Univ Press, 1992)
Human language is a relatively recent evolutionary innovation that came about when speech and syntax were added to older communication systems. The function of speech and syntax is to enhance the speed of communication: speech allows humans to overcome the limitations of the mammalian auditory system and syntax allows them to overcome the limits of memory.
Two principles are recalled. Natural selection acts on individuals who each vary: species that successfully change and adapt are able to maintain a stock of varied traits coded in the genes of the individuals who make up their population. The "mosaic" principle states that parts of the body of an organism are governed by independent genes. There are no central genes who control the overall assembly of the body.
Given these principles, two phenomena can be explained: a series of small, gradual changes in structure can lead to an abrupt change in the behavior of the organism; and an abrupt change in behavior may cause an abrupt change in morphology which causes the formation of a new species (at "functional branch-points").
The structure of the brain reflects its evolutionary history. The brain consists of a set of specialized circuits with independent evolutionary histories. Unlike modular theories such as Chomsky's and Fodor's, Lieberman's "circuit model" (derived from Norman Geschwind's connectionist model) assumes that the brain bases for language are mostly language-specific and mostly located in the newest part of the brain, the neocortex. The brain consists of many specialized units that work together in different circuits (the same unit can work in many circuits). The overall circuitry reflects the evolutionary history of the brain, with units that adapted to serve a different purpose from their original one. Therefore, rapid vocal communication is responsible for the evolution of the human brain.
The theory is supported by a wealth of anthropological and neurophysiological data (particularly from Broca's and Wernicke's experiments).
Besides language, the other unique trait of the human race (and therefore of the human brain) is moral code, in particular altruism. This is also a relatively recent development, and presupposes language and cognition.

Lightfoot David: THE LANGUAGE LOTTERY (MIT Press, 1982)
The book is basically an introduction to Chomsky's theories of language with an emphasis on biological aspects. First and foremost, Lightfoot examines how children can learn a language without significant instruction and despite a deficiency of experiential data. The only rational explanation is that an innate structure, a "universal grammar", guides the learning process.
Lightfoot applies Gould's theory of evolutionary change to linguistics: language changes gradually but every now and then is subject to catastrophic revisions.

Llinas Rodolfo & Churchland Patricia: THE MIND-BRAIN CONTINUUM (MIT Press, 1996)
A collection of papers by specialists on brain functions,

Lockwood Michael: MIND, BRAIN AND THE QUANTUM (Basil Blackwell, 1989)
Drawing from quantum mechanics and from Bertrand Russell's idea that consciousness provides a kind of "window" onto the brain, Lockwood offers a theory of consciousness as a process of perception of brain states.
By using special relativity (mental states must be in space given that they are in time), he leans towards the identity theory. Then Lockwood interprets the role of the observer in quantum mechanics as the role of consciousness in the physical world (as opposed as a simple interference with the system being observed).
Lockwood thinks that our sensations are intrinsic attributes of physical states of the brain. Consciousness scans the brain to look for sensations. It does not create them, it just seeks them.
Each observable attribute (e.g., each sensation) corresponds to an observable of the brain. The external world is a physical system in which a set of compatible observables is defined, whose state is therefore defined by a sum of eigenstates of such observables (i.e., by a sum of perspectives).
Lockwood mentions Deutsch David's "Quantum theory and the universal quantum computer" (1975), which generalizes Turing's ideas and defines a "quantum" machine in which Turing states can be linear combinations of states. The behavior of a quantum machine is a linear combination of the behavior of several Turing machines. A quantum machine can only compute recursive functions, as much as Turing's machine, but it turns out to be much faster in solving problems that exhibit some level of parallelism. In a sense a quantum computer is capable of decomposing a problem and delegating the subproblems to copies of itself in other universes.

Loritz, Donald: HOW THE BRAIN EVOLVED LANGUAGE (Oxford Univ Press, 1999)
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Lotka Alfred: ELEMENTS OF MATHEMATICAL BIOLOGY (Dover, 1925)
One of the very first studies that tried to formalize biosystems. His "maximum energy law" states that the survival of an organism depends on energetic output (as in growth and reproduction). Lotka also thought that biological evolution is a consequence of the second law of Thermodynamics.

James Lovelock: GAIA (Oxford University Press, 1979)
Lovelock views the entire surface of the Earth, including "inanimate" matter, as a living being (which in 1979 he named "Gaia").

Luger George: COMPUTATION AND INTELLIGENCE (MIT Press, 1995)
Seminal papers by Turing, Minsky, McCarthy, Newell, Schank, Brooks.

Luger George: COGNITIVE SCIENCE (Academic Press, 1993)
An introduction to the field.

Lukaszewicz Witold: NON-MONOTONIC REASONING (Ellis Harwood, 1990)
A formal survey of mathematical theories for nonmonotonic reasoning.
After an introduction to monotonic logic (first and second order), the book delves into nonmonotonic logics: Sussman's MICRO-PLANNER, Doyle's and de Kleer's truth maintenance systems, Mc Carthy's circumscription, McDermott and Doyle's modal logic, Moore's autoepistemic logic, Reiter's default logic and the closed world assumption.

Lycan William: LOGICAL FORM IN NATURAL LANGUAGE (MIT Press, 1984)
Lycan's theory of linguistic meaning rests on truth conditions. All other aspects of semantics (verification conditions, use in language games, illocutionary force, etc) are derived from that notion. A sentence is meaningful in virtue of being true under certain conditions and not others.
This is consistent with Davidson's program of assigning meanings to sentences of natural languages by associating the sentences with truth-theoretically interpreted formulas of a logical system (their "logical form"). Lycan basically refines Davidson's metatheory. Instead of assigning only a pair of arguments to the truth predicate, Lycan defines truth as a pentadic relation with reading (the logical form), context (truth is relative to a context of time and speaker, as specified by some assignment functions), degree (languages are inherently vague, and sentences normally contain fuzzy terms and hedges), and idiolect (the truth of a sentence is relative to the language of which it is a grammatical string).
Lycan argues that pragmatics (implicatures, presuppositions) should be kept separate from semantics. Context determines the interpretation of a sentence at several levels: it singles a logical form out of a set of potential candidates; it completes its proposition by binding all free variables; it provides a secondary meaning (e.g., implicatures); it clarifies lexical presumptions; and it determines the illocutionary force.
Lycan defends truth-condition semantics against the most common attacks, in particular against Quine's theory of indeterminacy and Dummett's antirealism.
Lycan finally presents a cognitive architecture based on a version of humuncular functionalism.

Lycan William: CONSCIOUSNESS (MIT Press, 1987)
Lycan reviews behaviorist and dualist theories of the mind, then focuses on Dennett's homuncular functionalism and defends it against its critics.
Lycan thinks that, besides the low level of physiochemical processes and the high level of psychofunctional processes, Nature is organized in a number of hierarchical levels (subatomic, atomic, molecular, cellular, biological, psychological). And each level is both physical and functional: physical with respect to its immediately higher level and functional with respect to its immediately lower level. Going from lower levels to higher levels we obtain a physical, structural, description of nature (atoms make molecules that make cellules that make organs that make bodies...). Backwards we obtain a functional description (the behavior of something is explained by the behavior of its parts).
The aggregative ontology ("bottom-up") and the structured epistemology ("top-down") of Nature are dual aspects of the same thing. The apparent irreducibility of the mental is due to the irreducibility of the various levels.

Lycan William: MIND AND COGNITION (MIT Press, 1990)
A massive collection of articles on theories of the mind. Homuncular functionalism is championed by Dennett and Lycan. Eliminativism is presented by Churchland and Feyerabend. Language of thought (Fodor), folk psychology (Stich), qualia (Block) are also discussed.

Lycan William: MODALITY AND MEANING (Kluwer Academic, 1994)
Lycan presents a theory of possible individuals and possible worlds in which a world is viewed as a structured set of properties. A number of philosophical puzzles are examined from a very technical perspective.

Lycan William: CONSCIOUSNESS AND EXPERIENCE (MIT Press, 1996)
It is mainly a defense of the materialistic philosophy of mind and a reply to Colin McGinn's thesis that consciousness cannot be understood by beings with minds and bodies like ours. "Conscious awareness is internal monitoring" as proved by the fact that most of our mental life is unconscious, even if we are conscious of part of it. Following Locke, consciousness is a perception of our own psychological state, of what is going on in the mind (Kant's "inner sense"). Lycan defends his position against various attacks.

Michael Lynch: THE NATURE OF TRUTH (MIT Press, 2001)
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Lynch, Michael: THE NATURE OF TRUTH (MIT Press, 2001)
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Lyons, William: APPROACHES TO INTENTIONALITY (Oxford Univ Press, 1998)
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Lyons John: SEMANTICS (Cambridge Univ Press, 1977)
A discussion of semantics within the framework of semiotics, i.e. taking language as a semiotic system.
Lyons discusses behaviorist semantics, logical semantics (model-theoretic and truth-conditional semantics, reference, sense and naming) and structuralist semantics (in particular semantic fields and componential analysis).
The second volume is more specifically linguistic, dealing with grammar, deixis, illocutionary force, modality.

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